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Objective Reviews & Commentary - An Engineer's Perspective

April 8, 2011

Beyerdynamic DT 770 Pro 80 Review

beyer dt770 benchmark

NOT MY USUAL FARE (revised 4/23): Generally I’ve been sticking to reviewing electronics as it’s easier to provide objective measurements and directly compare performance. I happened to give the Beyerdynamic DT 770 Pro 80 headphones a listen at a dealer and liked them enough to bring them home. They turned out to be an interesting example of how different sources can significantly change headphone sound.

REVIEW UPDATE 4/23: After living with the DT 770 Pros for another few weeks, and having a new “reference headphone” to compare them against, I’ve revised several of my comments in this review. I’ve also incorporated feedback from others. As happens with subjective reviews, it’s easy to let some aspects of a product (such as being really comfortable) bias or mask your subjective opinions of other aspects of the product. Motivation to write a long review comes easier when you’re enthusiastic having just listened to something new—hence all the reviews published soon after a product’s purchase. But it’s more realistic to live with gear long enough for the “newness” to wear off. And, in hindsight, that’s what I should have done here.

WHO’s BEYER? Beyerdynamic is the other popular German headphone company. They’re not nearly as well known among consumers as Sennheiser but they still have a loyal following—especially among musicians and professionals. AKG used to be almost German (Austrian) but is now a Harman International USA brand.

CIRCUM WHAT? The DT 770 is a true circumaural headphone. That’s a fancy way of saying they completely cover the ears. Anything resembling a full size headphone is often lumped into this category, but many still rest at least partly on the ears rather than over them. A good example is the popular Sony MDR-V6 (MDR-7506). They have shallow ear pads and rest mostly against your ears rather than your head. The Beyers pretty much leave my ears alone.

THE BASICS: The DT 770 Pro 80s are surprisingly lightweight (about 9 ounces) full sized headphones intended mainly for studio use. But they’ve also found a loyal following among some home listeners. The rated impedance is 80 ohms and they have an “SPL” rating of 96 dB SPL. Those two numbers mean they’re a bit marginal for use with most portable players (see Headphone Impedance). There is a better DT770 version for portable use. More on that later.

CLOSED MINDED: Full size circumaural cans come in two distinct flavors—open and closed. Most of the best sounding headphones are open to varying degrees. This allows the driver to be less affected by whatever is behind it. At least in theory, open back headphones have fewer reflections and resonances to color the sound. The downside is they let the music leak out which might disturb others. They also let more outside sound in. For some, however, closed cans have practical advantages.

ISOLATIONIST TENDENCIES: Most closed full size headphones don’t isolate as much as some might expect. They’re significantly better than open backed headphones but the best sounding and most comfortable closed headphones tend to have less isolation for some good reasons. For one, they don’t “clamp” the head tightly. While this greatly improves comfort it also lets more noise in. And they usually design the ear pads to intentionally “leak” as this helps vent the chamber between the transducer and the ear for more accurate sound. The ones that act like hearing protection muffs sound significantly worse. The special “M” high isolation version of the DT 770 is a good example—they don’t get good reviews for sound quality and are not as comfortable. If you want both great sound and high isolation, in ear monitors (IEMs) such as those from Shure and Etymotic are the best option. But they have their own downsides.

WHY THE DT 770? I need to listen to headphones for extended periods while not bothering others. And I’m often looking to filter out annoying background noise. With closed back headphones you don’t have to crank up the volume as high to drown out other sounds. That helps save your hearing and also makes for less listening fatigue over the long haul. Serious comfort is a must for listening hours at a time. I have several IEMs, and they’re great for flights, the gym, etc. But my ear canals get sore with long and frequent IEM use. They’re also a hassle to take in and out to talk to others, answer the phone, etc. So that leaves full size circumaural closed cans—like the DT770s. And if you want good sound and genuine comfort, the list is fairly short.

SOME COMPETITION (updated 4/10): The DT 770, with a $200 street price, has some significant competition. The ones I’ve heard are:

  • Sennheiser HD 280 Pro – You see these recommended everywhere. They’re reasonably priced with a street price around $100. They’re nicely made, fold up, and provide more isolation than many closed headphones. But, like many closed cans, they don’t really sound very good. The also have high clamping pressure, and the ear pads/ear cups are not really big enough to fully enclose most adult size ears without putting pressure on the ear itself. So many, me included, find them rather uncomfortable for long term regular wear. I own the HD280 and I’ll comment more on the sound quality later. They’re 64 ohms and work OK with some portable gear. Sennheiser doesn’t provide a typical sensitivity rating which makes directly comparing their efficiency to other manufactures difficult. 
  • Denon AH-D2000 – I own these and have spent a lot of time with them. For a closed headphone they’re relatively accurate and neutral sounding. They’re more comfortable than the HD280 but they’re relatively heavy and have oddly shaped ear pads that, despite being very soft and well made, put some pressure on the ears that gets annoying after a while. They also have a relatively stiff cloth covered cord that doesn’t stay out of the way very well. They’re 25 ohms with a very efficient 106 dB sensitivity rating so they work with portable gear but readily reveal flaws in a portable player or lossy MP3 track. They’re also nearly twice the street price of the DT 770s at around $350.
  • Audio-Technica ATH-M50 – Like the Beyer DT 770 Pros, these $150 cans are designed for studio use. They have a fairly loyal following and I think sound much better than the HD280s above. The bad news is they suffer from what I call “Shallow Ear Cup Syndrome” . There’s almost no “depth” to the inside of the ear cup once the earpads compress against your head and this leaves the ear itself squished up against a thinly padded area that protects the driver. They also clamp with enough pressure to bother many people after a while. If you don’t need to wear them for long periods, or have tough ears, they’re worth checking out. I had a pair of these for a short time and discuss their sound later. They also have a relatively low impedance at 38 ohms and high sensitivity of 99 dB making them a decent match for portable listening without using an amp.
  • Sony MDR-V6 (and the very similar MDR-7506) – These are the cheapest of everything here—about $80 street price. And they sound better than the HD280s But they suffer from Shallow Ear Cup Syndrome worse than the M50s above and sound artificially bright. Some suggest different earpads help make them more comfortable. I own a pair and never use them anymore because I can’t stand to wear them for more than an hour or so. They’re rated at 63 ohms and 106 dB sensitivity and work reasonably well with portable gear.

DT 770 CONFUSION: Beyerdynamic’s product managers have not made things easy. While nearly all the above headphones come in just one version, the DT 770 can be had in no less than 7 current versions:

  • DT 770 Pro 80 - Straight cord 80 ohm
  • DT 770 Pro 250 - Coiled cord 250 ohm
  • DT 770 M - High Isolation 80 ohm
  • DT 770 Edition 32 - Premium home version 32 ohm (portable use)
  • DT 770 Edition 250 - Premium home version 250 ohm
  • DT 770 Edition 600 - Premium home version 600 ohm
  • DT 770 Manufaktur 32, 250, 600 - Custom ordered from factory ($300)

And to make it more confusing, the “Edition” versions are also randomly called “Premium” or simply “DT 770”. And, from what I gather, still different DT 770 versions were previously offered. Choice is good, but Beyer might have gone too far.

WHAT’S THE DIFFERENCE (revised 4/9)? BIG DISCLAIMER HERE… I’ve only heard the DT 770 Pro 80 personally. But here’s what I’ve been able to figure out from the Beyer website, other reviews, etc:

The Pro versions use a cheaper looking plastic ear cup, have slightly more clamping pressure, and are made to be more rugged. The street price on the home/premium/edition series are at least $50 more. The “Manufactur” version is a custom factory order program from Beyerdynamic. You can pick options, colors, etc. and in a month or two have exactly the headphones you want. Well, perhaps not exactly, as they don’t offer the 80 ohm version for the Manufactur program. There are four different impedances available and, while I’ve only heard the 80 ohm Pro version, here’s my best guess at some of the differences:

  • 32 Ohm – Designed for use with portable gear like an iPod. They supposedly sound similar to, but not as refined as the 80 ohm version reviewed here.
  • 80 Ohm – The apparent favorite among people who like more bass in their headphones. They’re only available in the pro versions.
  • 250 Ohm – In the pro version, these have a coiled cord and Beyer says they’re intended for mixing music. Reviews and published measurements indicate they have less bass than the 80 ohm and 32 ohm versions. They’re best used with a source intended to drive high impedance headphones.
  • 600 Ohm – These are only available in the home version and, based on published frequency response measurements, have much less bass than the other versions. They’re intended for use with a dedicated headphone amp or other source that can handle their unusually high impedance.

WHICH ONE IS BEST? I chose the Pro 80 for several reasons:

  • They’re what the store stocked, and hence what I listened to
  • I prefer a straight cable (the Pro 250 uses a coiled cable)
  • They’re still (barely) usable with portable gear (the 250 and 600 are not)
  • Beyer doesn’t make the home “Edition/Premium” version in 80 ohm
  • They’re $50+ cheaper and more rugged than the home “Edition/Premium” versions

But your needs might be different. If you like to crank it up and want to use an iPod or other portable, the 32 ohm Edition is the best choice. If you don’t like as much bass emphasis and have a good source that can handle high impedances, the Edition 600 would be a better choice.

THE CABLE: The 80 ohm versions have a fairly heavy duty and very long 3 meter cable (about 10 feet) wired to the left ear cup. That generous length is good if you like to wander around while wearing headphones, or bad if you have to find something to do with the excess. The 250 ohm version has a coiled cord that supposedly extends to the same length. I personally don’t like coiled cords as they tend to weigh more, pull on your head and are more microphonic (rub against things and create unwanted noises in the headphones). Because the straight cable is very slick and smooth the microphonics are fairly low. There’s a 3.5mm mini plug with a screw on 1/4” adapter. The strain reliefs at both the plug and headphones are very robust and well designed. I’m guessing the cable will last a long time which is a good thing as it doesn’t unplug from the ear cup. This is the sort of cable you can run over with your office chair multiple times and not hurt it.

CONSTRUCTION: The black steel head band seems very tough as do the hinges and adjusting clips. The ear pads and headband pad are easily replaceable. Beyer has black velour and black vinyl pads also available and you can find third party ear pads in real leather and with gel instead of foam.

ERGONOMICS & COMFORT: These are seriously comfortable headphones for three reasons. First they don’t suffer from the dreaded “Shallow Ear Cup Syndrome” like many of their peers. There’s actually room for a human size ear inside (see the pic further down). They’re also fairly light at only about 9 ounces. By comparison the Denon AH-D2000 is about 13 ounces. The ear cushions are covered with a soft velour that adds to the comfort as, unlike vinyl, there’s no sweat build up. While the Pro versions supposedly exert about one third more “clamping pressure” they still sit relatively lightly on your head—especially compared to the Sennheiser HD280. And if you want lighter still, you can bend the steel headband as desired. Finally the bottom of the headband is well padded with soft padding. So unlike say several models (AKG comes to mind), there are no pressure points on the top of your head. The only obvious downside is they don’t fold up for travel, and if you’re a DJ, you can’t swivel the earcups to use one at a time.

beyer line up

SOUND QUALITY (revised 4/23): After 48 hours of continuous break in (like breaking in a pair of new shoes it can, in theory, make a difference due to the initial stiffness of the moving diaphragms), I listened to the DT 770s mostly using a Benchmark DAC1 Pre as the source with a variety of material sourced from my PC and a Slim Devices Transporter. I also used an iPod Touch 3G and experimented with the output impedance on the DAC1. See the Tech Section for more. I compared the Beyer’s to three other popular closed back headphones--the Sennheiser HD280, Denon AH-D2000 and Audio-Technical ATH-M50. I also compared them to my Sennheiser HD590 open back headphones. I only had the ATH-M50s a short time so I had less experience with those.

TWO CAMPS: There are two fairly distinct groups of headphone users. A lot of people, especially those using portable players, are used to an “enhanced” sound with emphasized bass and highs. Many manufactures create a “V” shaped frequency response that’s lowest in the middle and rises strongly at both ends of the spectrum. When you select the “Rock” or “Pop” EQ preset on many portable players, you get just such a “V” shape. If that’s what you’re used to, accurate (i.e. relatively “flat”) headphones can sound boring—at least at first. So most portable players, iPods included, come with headphones with at least a somewhat “V shaped” response. But another group of listeners prefers more accuracy. More accurate headphones tend to be much less fatiguing over time and more natural. Plus, you can always add EQ to punch up the bass and/or highs if you want. Headphone manufactures are put in the difficult position of either offering different models to appeal to the different camps, or trying to compromise with a sound that tries to please both groups.

BEYER’s COMPROMISE? The DT 770 is allegedly for professional studio use and one might expect them to be relatively accurate. But I think Beyerdynamic recognizes many musicians, like much of the public, have come to expect enhanced bass and highs. Musicians buy iPods too. So it’s my guess they tweaked the 770 to appeal more to the tastes of pop/rock musicians while still trying to keep them accurate enough to allow use by recording engineers, etc. Sometimes compromise is a good solution, and sometimes it messes up a good thing.

BASS PERFORMANCE (low impedance source): Let’s say you take your boss to lunch in your polite four door sedan. Driving gently, there’s only muted burble from the exhaust hinting the car isn’t your mother’s Camry. Little does your boss know it has 370 horsepower and could pin him in his seat if you wanted to indulge your inner child with your right foot. That’s kind of how the bass is with the Beyers. Listening to a polite string quartet, there’s only a slight hint of the 770’s reputation for being “bass heavy” but play a hip hop track and hang onto your teeth. It’s Jekyll and Hyde. The Beyers have, by far, the most deep bass of all five cans I compared. In overall bass level with pop music, the rank is roughly DT770 > HD280 > ATH-M50 > D2000 > HD590.  But that’s a bit misleading as the DT770, for example, has less upper bass than the say the HD280. The HD280 makes that string quartet sound thick and muddy. The 770 has a very “punchy” bass that only really calls attention to itself when there’s significant deep bass in the music. Male vocals, for example, remain relatively accurate. The overall quality of the bass is better than I expected but it turns out that’s partly related to what they’re connected to.

BASS PART TWO (high impedance source): Based on what I’d read, I expected the bass of the DT 770 to be less controlled than it is. I wrote an article about how source impedance interacts with headphones to change their bass performance and wondered how the 770’s performance would change using a higher impedance source? The answer is quite a bit! Using one standard of 120 ohms, the formerly tight punchy bass of the 770 became more bloated and warm with less deep bass extension. The bass peak now reached up high enough to make male vocals sound thick. In short, the really deep rattle your teeth performance was diminished and replaced by a much less pleasant “boomy” bass peak. I wonder how many who dislike the 770’s bass heard them from a higher impedance source?

MIDRANGE (revised 4/23): The midrange of the DT770, like most closed cans, suffers a little. It’s a bit recessed and sounds a kind of “nasal” on some recordings. But these complaints are relative. The midrange is far more pleasant than the HD280 for example. The M50 sounds warmer (some might say too warm) through the midrange and the $350 Denons still have the best midrange of any closed cans I’ve heard. But the 770’s more laid back mids can sometimes be a benefit on poorly recorded, mastered, and/or ripped material. They’re less “in your face” than the more forward sounding Denons and hence are more forgiving. I rather like the 770’s midrange on a lot of male vocals while on female vocals they sound a bit “dark”. The midrange is somewhat similar to the open HD590 which is also a bit recessed (and some would say “dark”). If you’re a stickler for accurate midrange, I’d suggest the D2000s (or perhaps one of the other Denon models, Shure SRH 840, etc.).

HIGH FREQUENCIES: The 770’s highs are not as bright, revealing, or accurate as the more expensive Denon's. They’re closer to the M50s but the highs have a slight “enhanced edge” to them--not in a harsh way. It’s more an “artificial” sort of enhancement. To use a visual analogy, if you’ve ever seen an over sharpened video or picture, that’s similar to what I’m talking about. Initially it’s impressive, but over time, you realize it’s partly fake detail. The trick worked well enough to get me to take them home from the store. The 770’s highs, despite the “edge”, are still more forgiving of poor source material than the Denon's. And the 770’s highs sound better than the HD280’s. So pick your poison.

SOUNDSTAGE: To my surprise, the Beyers are far more open than the Denons. They also easily beat the M50 and HD280. The Beyer soundstage is deeper and wider and there’s more space between instruments--more like the open backed HD590. More of the ambience comes through. It’s another reason they initially impressed me.

EFFICIENCY (sensitivity): The DT 770s were the least efficient of the five headphones by several dB followed by the HD590s. The other three (Denon, M50 and HD280) were within a few dB of each other at the same volume setting.

PORTABLE COMPATIBILITY: With my iPod Touch 3G, the Beyers sound good on typical heavily compressed pop material but won’t get uber-loud. On really dynamic material, such as Flim & The BB’s Tricycle, the iPod (with its 7 ohm output impedance) clearly lacked bass punch compared to the Benchmark as the bass notes were clipped by the player at higher volumes. The Sansa Clip+ and Fuze did marginally better than the iPod but still fell short. Any portable device conforming to the new EU hearing protection regulations would be seriously underpowered. You can take these headphones with you (if you have room) and they’ll work OK from some portables. But to hear what they can really do, you need a low impedance source with enough beans. See the Tech Section for more details. The 32 ohm version of the 770 would be a much better match for portable use.

MAX SPL: The 770 will play cleanly well into hearing damage levels. If you feed them large amounts of deep bass at high levels, you’ll hear some audible distortion as the drivers run out of excursion (approach their limits of travel). You also get significant intermodulation distortion. This is true to varying degrees for nearly all dynamic headphones but the Beyers are perhaps a bit worse than average in their price class.

SOURCE MATERIAL: The DT 770 is more revealing than the HD280 but less so than the D2000. They’re similar to the M50. If you take them for a test drive I’d suggest using a wide variety of material and not just well recorded audiophile demo stuff. The highs, in particular, don’t get along with some source material.

OVERALL SOUND (updated 4/23): The nearly twice as expensive Denons are much more accurate than the 770s and still the best sounding closed cans I’ve heard on good source material. But the Denons ruthlessly reveal flaws and have a more “in your face” sound. The Beyers sit you a few rows further back in the venue, are more spacious, and try to offer some of the bass and treble “enhancement” many have grown used to. Some are likely to enjoy the punchy deep bass and enhanced highs. The 770's extra bass, at least driven from the Benchmark DAC1, doesn’t get in the way as often as I expected. But those who seek accuracy may find it excessive. The rest of the tonal balance isn’t perfect but, among closed comfortable cans, they’re better than average. The 770s, for example, blow away the well regarded HD280s in virtually every way. So if you like the HD280s, you’ll probably love the 770s.

beyer dt770 earcupTHE GOOD:

  • Very comfortable with room for an actual human ear inside
  • Spacious, engaging sound that’s “enhanced” in ways some might like
  • Serious deep bass without a lot of “muddy boom”
  • Laid back midrange is more forgiving on poor source material
  • Closed back to not disturb others and increase isolation
  • Solid rugged design
  • 80 ohm impedance allows some portable use at lower volumes

THE BAD:

  • Too much deep bass for those who prefer more accuracy
  • Boomy bass with high impedance sources
  • Midrange too laid back for some tastes
  • Somewhat uneven highs create a fake sense of detail
  • Plastic ear cups look kind of low-rent
  • Not the best match for some portable gear for louder levels

BOTTOM LINE: There are not many closed can I can wear for hours on end. The Denons flunk that test where the DT 770s pass it with comfy flying colors. And they’re also more forgiving of poor source material than the Denons. They sound similar to the Audio-Technica M50s but are much more comfortable. They’re well made and better than the HD280s in every way (except portability). With a low impedance source, the solid, deep, punchy bass can be fun with the right music. And some should enjoy the recessed midrange and “enhanced” highs. Beyer did a reasonably good job of trying to keep them from sounding “too boring” for those who are used to enhanced bass and highs. And they did it in a way that still leaves most of the frequency spectrum relatively unscathed. Some might find the DT 770 a perfect compromise but those seeking serious accuracy should look elsewhere.


TECH SECTION:

OBJECTIVE MEASUREMENTS: I’m big on hard numbers, but I don’t have a HATS (Head And Torso Simulator) or even a fake head with an embedded instrumentation grade microphone. So it would be difficult to make meaningful frequency response, distortion, etc. measurements as I would probably have a hard time even reproducing my own measurements let alone comparing those made by others. Headphones (along with speakers) vary widely in sound and the desired frequency response tends to be more subjective.

HEADROOM TO THE RESCUE (added 4/14): Being unable to make my own measurements, the best ones I know of are at HeadRoom. Here are 4 of the headphones discussed in this review:

HeadRoom DT770 vs HD280 vs ATH-M50 vs AH-D2000 Frequency Response

The HD280 has an upper bass dip where the others are flat or have a rise. And the M50 and D2000 have similar bass performance. If you scroll down within the comparison window, you can also view distortion, impedance, isolation and the square wave response. The HD280 has a severe dip in the extreme highs. But, otherwise, the four headphones are more similar than different. The Denons are the flattest overall. Looking at the 50 hz square wave response, the DT770s are the winner:

HeadRoom DT770 vs HD280 vs ATH-M50 vs AH-D2000 Square Wave Response

The “flatter tops” (in blue) of the DT 770 square wave response indicates flatter low frequency response than the M50 or Denon. And, while to many ears, the 770s have exaggerated bass, to the microphone, the bass is more accurate than the other three.

It’s worth noting not everyone’s head and ears are shaped the same as the artificial one used by HeadRoom. And that will change the results. And everyone has their own preferences and hears things differently. But the artificial head, microphone, and test gear at least attempt to provide a fair comparison between headphones. Assuming the measurements were made correctly it’s safe to assume, for example, the DT770 and HD280 have more bass than the other two based on the measurements. And indeed that’s what I heard and most others are likely to hear. So there is some valid correlation. But the graphs alone can’t always tell you which one will sound the best.

HEADPHONE IMPEDANCE: The DT 770 Pro 80 is rated at 80 ohms and measured somewhat above that. At the lowest point they’re about 83 ohms with a bass resonance peak (in free air, not on a head) at about 50 hz and nearly 110 ohms. They also exhibit the typical rise at the high end due to voice coil inductance. The phase shift (in white) is very linear and gradual making them an easy load:

Beyerdynamic DT 770 Pro 80 Impedance and Phase

IMPEDANCE INTERACTION: As discussed in the subjective review, the Beyer’s bass was well controlled when driven from the near zero ohm output of the Benchmark DAC1 Pre. The IEC standard from 1996 (before portable digital players became seriously popular) specified a 120 ohm output impedance. I put 120 ohms in series with the DT 770s on the Benchmark and the sound changed significantly. 120 ohms is enough to seriously degrade the electrical damping of the driver which raises the Q. That, in turn, causes the bass to peak more, at a higher frequency and roll off sooner (less deep bass). The bass also ends up less damped overall and hence less controlled and less “tight”. That’s exactly what I heard. The bass got more muddy, boomy and didn’t reach as low. This is discussed further in the Impedance Article.

The 120 ohm source also creates a frequency response error in the signal driving the headphones. Here’s the signal from the Benchmark at zero ohms in blue, and from a 120 ohm source in yellow. There’s almost 1.5 dB of variation. Note this is the electrical input level, not the acoustic output of the headphones but it will still cause a similar response variation in the acoustic output compared to a zero ohm source (in addition the the headphone’s regular response variations):

Beyerdynamic DT 770 Pro 80 Zero Ohm Source (blue) 120 Ohm IEC Source (yellow)

SOURCE IMPEDANCE SUGGESTIONS:  If you’re not a fan of bloated bass, the lower the output impedance the better with the Beyer’s. This increases the electrical damping and tames their bass boost. When I tried them with my iPod Touch 3G, which is around 7 ohms, the bass lost some punch (also possibly due to the peaks being clipped). And it gets worse as you go up in impedance from there.

SOURCE DRIVE LEVEL: On highly compressed pop music I cranked up the Beyer’s to about as loud as I would normally go and measured the signal on a scope while listening. The peaks were hitting +/- 400 mV which is only about 280 mV RMS. Even most portable devices can manage that. But, playing material with a wider dynamic range at loud levels, I needed up to 3.5 volts peak-to-peak which is about 1.2 volts RMS. The $20 FiiO E5 can manage about 1.3 volts RMS and it got plenty loud even on highly dynamic material but the Beyer’s likely deserve better than the E5.

To translate this into power output, at a more-than-needed 1.5 volts RMS, that’s 70 mW into 32 ohms, 28 mW into 80 ohms, and 9 mW into 250 ohms. Sources rated somewhere in that range should have enough cajones to do the job without clipping or running out of gain.

POWER HANDLING: Beyer rates the 770 Pro at 100 mW. For the 80 ohm version, that’s 2.8 volts RMS and would be uber-loud. The driver, however, runs out of excursion well before that at low frequencies.

SOURCE QUALITY: As mentioned in the review, while not the most revealing cans on the planet, the Beyer’s are well above average. So poor quality sources, poor recordings, lower bit rate MP3’s, poorly designed amps/DACs, etc. are revealed for what they are. The Beyer’s sometimes take a bit of the edge off, but they don’t “gloss over” defects the way a lot cheaper headphones do.

TECH SUMMARY: There were no real technical surprises except I wonder how much of the 770 Pro 80’s reputation for unpleasant bass is from people using higher impedance sources?

106 comments:

  1. Hey man, nice review! I have the exact same phones and they rock. I started with the Sony V6 but they made my ears sore and needed bass boost to sound good but the Beyers are awesome with everything set flat and I forget I they are on. They also leak less sound than the Sonys scoring points with my officemates.

    But you should make it more clear its not just portables that have trouble with the Beyers. My Macbook and iMac at work can't drive them well either so I had to pop another hundred for an amp which kinda sucked. But no regrets as I've probably spent a 1000 hours listening to them nearly everyday at work over the last year.

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  2. Thanks for the comments and good point on the Macbook issue. I'm going to be publishing an article on PC headphone outputs (including a Mac Mini) that should help.

    My Sony's don't get much use these days. How much they "rub you the wrong way" comfort-wise seems to depend on the shape of your ears. For some they're comfortable enough and a bargain.

    The bass issue comes down to personal preference and is a polarizing topic. In the case of the DT770's driven by a decent low impedance source, I think some are throwing out an otherwise attractive baby with the bass-enhanced bathwater. But we all like what we like. For me, the 770's fill a certain niche nicely. If you like deep bass, they're perfect for what you describe--wearing them all day long at work.

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  3. You have previously criticised the religious nature of the audiophile market and gear reviews which tend to rely on rituals and subjective feelings instead of measurements and tests. Yet in your own review you use expressions such as "fun" and "engaging" and even mention headphone burn-in. I'm a bit confused here.

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  4. Traf, Thanks for the feedback. I tried to make it clear from the start this isn't a typical review for me. The "fun" and "engaging" were quotes from others about the DT770's. I've added a link in the Tech Section to more objective data.

    Break-in is real for headphones and speakers (unlike say cables). The diaphragms have a "suspension" allowing them to move and can often be overly stiff when they are new. I should have done it here, but I've seen a shift in the impedance plot after break-in. That peak you see at 60 hz in the Beyer's impedance is partly from the stiffness of the suspension and can change from brand-new to broken-in.

    One of my goals for this blog is correcting gear myths I encounter. For example, the $20 FiiO E5 headphone amp doesn't have a very good reputation, but my testing reveals its probably a lot better than many realize. In the same way, I believe the DT770's are better than some might otherwise suspect. But, ultimately, the sound of headphones varies much more widely than the sound of say headphone amps.

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  5. Could you perhaps do some tests and an article on headphone burn-in? Because the tests by some other people (Dave Rat for example, search for it on youtube) suggest the frequency response doesn't change at all.

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  6. Traf, it likely depends on the headphones. I missed my chance to test the impedance before and after with the DT770's but I have some new Sennheisers on the way and will try with those.

    Dave Rat probably knows 100 times more than I do about a lot of prosound topics, but frankly, his equipment and measuring techniques for headphones are a bit sketchy. His big headphone shootout is an impressive effort but it's full of technical flaws and issues. He just doesn't have the right gear to try and measure headphone frequency response or distortion properly. The fact he just rested the HD280's differently on his desk and it made a huge difference in how they performed on his tests should tell everyone something. Sine waves just don't work well for acoustic measurements (versus electrical ones), he doesn't have a simulated head/ear, and his equipment is seriously out of date and limited.

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  7. It's also worth noting, unlike lots of other audiophile preferences, break-in is literally free. As long as you don't get carried away, it does no harm.

    This link (scroll to the bottom) shows break in measurements of a speaker driver after 0, 30, 50 and 70 hours. There's a big change from 0 to 30 hours, a small change from 30 to 50 hours, and hardly any change from 50 to 70 hours. Dynamic headphone drivers like in the DT770's are just smaller versions of what's measured here:

    http://www.vikash.info/audio/audax/

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  8. For the "shallow ear cup syndrome", cut a ~6cm piece off an old AC or CAT5 cable, and stuff it under the ear pads, at the backside of your ears. That should fix that comfort issue for good. Here's some photos of that mod: http://anythingbutipod.com/forum/showpost.php?p=542412&postcount=37

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  9. Burn-in in general has a very serious logic flaw for which I am yet to see a plausible explanation from the people who believe in burn-in. If a material or a component is supposedly burned in over time, how is it possible for the phenomenon to stop exactly at the right moment? If something really changes, it should change indefinitely when in use. That just does not happen and ergo, speaker or headphones or electronics burn-in is just another myth.
    Here is a somewhat different look http://www.audioholics.com/education/loudspeaker-basics/speaker-break-in-fact-or-fiction
    And also some interesting stuff here http://www.matrixhifi.com/ENG_contenedor_rodajealtavoces.htm

    Of course, there are measurable differences in some variables as shown by Mr Vikash, but these are most probably caused by the fact, that during burn-in gear is IN USE and under stress. A lot of serios stress at least in the test of Mr Vikash (15 or 20 Hz to Xmax or xmech, which is kind of crazy). Also there might be changes in temperature (definitely voice coil temperature with that amount of power and maybe also ambient temperature) which definitely causes changes in driver compliance. Mr Vikash should have done another set of measurements after the drivers were "rested". I'm sure I would be very reluctant to burn-in my speaker drivers for 70 hours with 15 or 20 Hz to Xmech. It is entirely possible to literally break your drivers doing so.

    In any case, it is at least certain that the changes in system response are minuscule, even when the changes in some measurable variables of compliance are as big as 20-30%.

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  10. Cer, thanks for the added comments. I agree the topic, like so many in the audio world, is not without controversy. I can say I've personally seen lasting changes in the T-S parameters of new drivers before and after break-in. And I'm not suggesting anyone push drivers to their Xmax for days on end. I suspect he was just trying to speed up the process.

    As to when to stop, as you can see in the data, the changes are greatest at first and get smaller over time. If you follow that trend break-in is largely self limiting.

    It's not unlike a new pair of shoes--they're kind of stiff when new but they break in and get softer and more flexible after some use. They don't magically go back to being stiff if you let them "rest". The spider and surround that form the suspension of many drivers are made from relatively similar materials to those used in some shoes.

    I think part of the problem here are the typical "extremist" views among those in this "hobby". The subjectivists tend to take little bits of objective truths and extrapolate them much further than they should (i.e. breaking in cables). And some objectivists, even when presented with hard data (as I've tried to do here), still want to discredit any audiophile belief they can.

    There is often middle ground between the two extreme points of view as I believe there is here. Break-in, where the physical properties of moving materials are involved, makes a significant and measurable difference. The break-in changes documented in T-S parameters can be readily shown to make an audible difference in the performance of a finished speaker. I know some claim that disappears if you let the speaker rest, and perhaps that's true with certain materials, but I've seen lasting changes.

    What I can't say is if break-in applies to the types of materials used in typical headphone drivers. But I'm in the process of testing that now and I'll report the results!

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  11. Hi NwAvGuy,

    I originally tried contacting you via e-Mail, but the contact form wouldn't clear for some reason, so I'll write here instead:

    I was wondering if you would allow me to translate some of the articles on your blog to a forum on a Korean website (www.goldenears.net) - the site is also based heavily based on measurements. I will be sure to link the source if allowed.

    Thanks,
    Silens

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  12. Silens, Please try to contact me again with the link on the right (i.e. http://nwavguy.blogspot.com/p/contact-nwavguy.html ). There was a Blogger format change that had black letters on a dark gray background making it hard to read. It should be fixed.

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  13. Howdy NwAvGuy,

    I really appreciate your blog. As someone who considers himself a budding audiophile, the information you have posted is extremely helpful.

    I was thinking of purchasing the DT770/80 in lieu of a Sony V6 I am returning (because of how fatiguing the sound is). I also wanted to purchase a portable amp/DAC to use with my aging thinkpad and with my 2nd gen iPod Touch. I listen mostly to electronica, classical, and hip-hop with some jazz and pop thrown in there every so often.

    My question for you is this: Will the Fiio E7 drive and pair with the DT770/80 well? I read on another forum that the E7 does not have enough power for these phones. That user was complaining that using the E7 with the Dt770/80 resulted in weak, muddy bass. If you think the E7 won't fit my proposed application, what other amp/DACs would you suggest I consider?

    One last question, how would you characterize vocals through these phones, with the recessed mids and all?

    Thanks so much for your time,
    Sam

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  14. Sam, after spending more time with them, I just revised the DT770 review and you might want to skim through the comments on sound quality. The 770's do have somewhat recessed mids--more so than I initially realized. They also have some high frequency anomalies that have become more obvious with time.

    I've fully measured the FiiO E7 and will be publishing the review soon. It has a very low output impedance and should drive the 770's to fairly loud levels with typical compressed pop material. If you listen to really wide dynamic range music (jazz, classical, etc.) the E7 might clip some of the peaks.

    That clipping might be the cause of subjective comments regarding "weak muddy bass" as I noticed the same thing using my iPod with the 770's. But it might also be someone who doesn't think a $99 DAC can do a good job (there are plenty such people). The E7 can.

    I would suggest if you like the overall sound, comfort, etc, of the 770's consider the 32 ohm version? The E7 should easily drive those well into hearing damaging territory.

    If you want really accurate midrange in a comfortable, closed, over-the-ear, full sized can, you might look into the Denon D1100. I haven't heard them but they're supposed to be in the same league as the D2000's. They're also easy to drive directly from a portable (no E7 required).

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  15. Hello, I really like your review. However, I am fairly new to the higher-end audio arena so I don't fully understand the impedance information. I just ordered the 80 ohm version, will an iPod Touch 1G be enough to drive them to around the most potential? I have a Fiio E5, would that fare any better? I will probably get the Fiio E11 later on but I don't want to have to use an amp if I don't have to.
    Thanks.

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  16. Jim, I'm not that familiar with the Touch 1G. I suspect the E5 will do slightly better. But it really will come down to what kind of music you like and how loud you like to listen. You might find the Beyer's are just fine without any amp. From what I've read so far about the E11 it should be fine. For home use, however, the E9 might be even better. But I haven't tested either of them.

    If the Beyer's don't play loud enough, you might consider returning them for the lower impedance version.

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  17. Nice review there. What was the chance of you /also/ owning some HD590s?

    Looks like the Beyers are less sensitive than their 96 dB/mW spec suggests (which is something that has been suspected for years). In theory, the 80 ohm ones should play as loud as the HD590s (97 dB/mW, 100 ohms) on a low-impedance source. Mind determining the difference?

    When I was checking sensitivity by ear, I got pretty consistent results using the old Scorpions track "Blackout". It has this kind of late-'70s rock sound, fairly wideband without too much going on towards the extremes of the frequency spectrum. (That even sounds OK on HD424s, which are seriously lacking in low/mid bass on other material.) Errors seemed to be no more than +/- 1 dB, plenty good enough for getting an idea of what's going on. (Mind you, that was on the Clip with its 1.5 dB volume steps, so display vs. setting can be off by 1 dB.)

    Speaking of HD590s, mind taking an impedance plot of these? I've been looking for one, like, forever. All I know is that DC resistance of my drivers is pretty much exactly 100 ohms. I guess max{|Z|} will be about 250 ohms. Yes, they should be a lot more fussy than those Beyers.

    I'm under the impression that your listening levels are a bit on the high side (which arguably isn't that bad for reviews, as you're closer to worst-case). I'm pretty much on the opposite side.

    For reference, my usual volume settings when running my Rockboxed Clip+ on HD590s (no EQ) in a quiet environment tend to vary between -25 and -29 dB on regular pop & rock, and more like -13 to -16 dB for classical symphonies. And that's with Replaygain sporting a Pre-amp setting of -4.0 dB to accomodate worst-case track dynamics including MP3 overshoot (all my tracks use RG).

    With the determined maximum undistorted sine level of 630 mVrms on that player, fullscale on a RG +0.00 dB track cannot be more than about 90 mVrms at the -13 dB volume setting (and -4 dB pre-gain). And that's pretty loud to these ears. No wonder, as it should give about 96 dB SPL on HD590s. (And real-life "fortissimo" RMS levels still are about 6 dB away from sine-referred fullscale, so it would be more like 90 dB SPL max in practice here. If it's not bass, that's plenty loud.)

    It would be interesting to know what your listening levels are under similar conditions. They would seem to be at least 10 dB higher than mine.

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  18. Stephan, thanks for your comments. I have an impedance/phase plot of the HD590's and would be happy to email it to you if you want to contact me using the link in the right hand column? They run about 105 ohms typical and peak at 200 ohms at about 120 hz.

    The replay gain headroom issue is an interesting one and something I hope to address in a future article. I listen at a variety of levels and have, on many occasions with both headphones and speakers, set up a fast scope to trigger if the level approaches clipping. It's a way to know if your amp is really up to the task with highly dynamic music or not.

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  19. Hi NwAvGuy

    im based in England and want to buy the Beyerdynamic DT770 PRO headphones, i will be using them to listen to Music on my iPhone 4 and my laptop and also into my Digital Piano and Keyboards for making Music in my Studio, which version would be best for me? 32ohms, 80ohms or 250ohms?

    thanks for your help

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  20. That's a tough call. I have no idea what sort of output your keyboards have. If I had to pick, I'd say 32 ohms. But I don't the cheaper tougher "Pro" version comes in 32 ohms? The 80 version should work reasonably well as long as you don't want it really loud.

    Wherever you buy them you might want to make sure returns are easy just in case.

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  21. i have never had headphone amps before, any idea what these headphones sound like with an iPhone 3GS or iPhone 4? i think i`ll take your advice and get the 80ohm versions
    i was thinking of getting the Fiio E9, would that be a good match?

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  22. The FiiO E9 has a 10 ohm output impedance which the DT770's are not crazy about. It makes the already enhanced bass a bit less controlled and more boomy (see my review).

    I would try them first without an amp and see what you think. I use mine with my iPod Touch 3G which is very similar to an iPhone 3GS and they work reasonably well. They won't get super loud but plenty loud enough for most casual use.

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  23. Great review! A question if I may - I have the Behringer UCA202 (50 ohm output) for mobile use, which you recommend be mated with headphones of at least 80 ohms, and which the DT-770's (83-110 ohms) just barely reach. The frequency deviation would be modest with this impedance pairing, but potentially the damping would suffer.

    Have you tried the DT770's with the UCA202 and noticed a significant problem with damping? I'm not a big bass-head, so I would not typically push it to the extreme. Thanks in advance for any insights!

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  24. I did try them with a 120 ohm source and the bass was bloated, boomy and not very nice. They really benefit from an output impedance as close to zero as possible. My rule of thumb is 1/8 the headphone impedance. So the max for the DT770-80 is 10 ohms. The UCA202 is five times higher.

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  25. Do you have any experience with the premium DT 770 either the 32 ohm or 250 ohm models?

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  26. Beyond holding a premium model in my hands I don't have any experience with them.

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  27. In part because of your excellent review, I just got a pair from the Beyerdynamic eBay outlet, much reduced in price ($90 shipped) and factory refurbished (cosmetically a 9 or so, and with obviously new pads and headband, and no apparent problems in performance). My guess is that they were demonstration models somewhere?

    My impressions match yours regarding their sonics and comfort. My Sansa Clip+ drives them pretty well, although high-decibel mayhem would require an outboard amp. On my 75 ohm output laptop, the bass is noticeably loose, while it is tight as a drum on the Clip+. I was delightfully surprised how un-closed they sound.

    So, thanks for the lead on a great pair of cans!

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  28. Kevin, You're welcome. I'm glad you like 'em and you got a screaming deal. They're pretty tough headphones so I wouldn't worry about buying refurbs. Since I did the review mine have had their share of accidental abuse and they're none the worse for it which is more than you can say for a lot of higher-end full size cans which can be fragile by comparison.

    I'm not sure how much, and what kinds of music you've listened to so far on the Beyers, but every now and then I come across something with well recorded and impossibly deep bass--the stuff you feel more than hear with a high-end subwoofer--and the DT770's can somehow deliver it in a way that defies belief.

    And yeah, if you put them on someone blindfolded, they'd never guess they were closed headphones. They're far more open and spacious than a lot of open back cans.

    They're a very different experience than my HD650s. I listen to them both regularly despite their dramatic differences. The DT770's get mostly used when I want more isolation but they're also my go to cans for when I'm in a bass lovin' sort of mood or want to listen to music they do an especially good job with.

    And the Clip+ is just amazing. Again, blindfolded, someone would think it was a high end portable costing far more and far larger in size. I bought another spare just in case Sansa stops making it and they get the replacement wrong (like they did with the Fuze+).

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  29. Bought the DT 770 Pro 80 Ohm model in Dubai for an over priced 800 AED (218 USD).

    First thing to notice, they're very very light. Can't actually review them since these are my first full closed headphones since my early '90's Aiwa's Sound GT earphones, that still work! :-D.

    First subjective impressions are positive. When listening to FLAC/MP3 content from the headphone output of the Creative Inspire T7700, with the Audigy 2 soundcard and the Audigy 2 breakout drive's headphone outputs.

    Alternative Hard Rock, Tribal house, Big Beat all sounds awesome. Best part is I can enjoy hard rock even at much lower volumes, than my speakers.

    I only noticed some distorted bass on the start of the The Crystal Method's American Way (flac), which sounds fine with my fifteen year old Aiwa mini-hi-fi speakers. Could be the track itself, not entirely sure.

    If you're an electronica fan and really want to be blown away by these headphone, listen to DI's Tribal house stream.

    I might end buying their in-ear models too for outdoor workouts, really really liking beyerdynamic. Many thanks for the review NwAvGuy :-D

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  30. Thanks IncidentFlux. Check out Blue Man Group "Persona" from their CD "The Complex". It has the sort of subterranean shake the room deep bass the DT770's pull off like no other headphone I've heard. Tracks like that have people taking the headphones off to hear the subwoofer in the room that's slamming their body with subsonic bass. But there is no subwoofer--just the headphones. Somehow the DT770's make you "feel" bass like that. It's kind of amazing.

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    Replies
    1. ...or Ja Rule's "Livin' it up"! I had to take the phones off several times when the Mr. Hyde persona kicked in. Just for the record you are spot on - you can actually use the 770-80's on mobile devices if the music is well compressed. I alternate on several devices but they're just fine on my iPhone 4 too (tight lows at 80% volume). I also did two 10 hour flights in the last two days and they were comfie for extended listening and blocked out most of the ambient sounds.

      Delete
  31. Thanks NwAvGuy.

    Well...I think I might get a DAC+Amp or just an amp to use with my Lenovo T400 laptop at work, which uses a Conexant 20561 SmartAudio HD sound. The bass just doesn't sound right.

    To complete the audio chain, I'm thinking of going for the expensive, but very positively reviewed USB CEntrance DACport (with amp).

    Or will a FiiO E11 amp be enough? Which I would also be able to use with my Nokia E71 or any portable player on occasion.

    I think the CEntrance DACport will be an appropriate pairing for these headphones in the long run.

    Thoughts?

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  32. I have nothing but respect for CEntrance. Benchmark licensed their high-res driver-less USB technology for the DAC1 products and, as my measurements have shown, it works very well. The DACport, with say an O2 amp, would be a killer combination for just about ANY headphone including the DT770. I've spent a long of time listening to my DT770's on my O2 and it's a great combination. The low output impedance of the O2 keeps the bass tight and the O2 doesn't even get remotely close to its limits in any way.

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  33. That's very reassuring, thanks.

    I will probably just go for the DACport alone, considering most of my audio source at work will be 256K+ bitrate MP3s and low res streaming radio stations. :-/

    How would you rate the FiiO E11 as just a on the road travel amp with the 770s? One of the reason I like the FiiO E11, is its replaceable Nokia battery.

    Hey you should do video reviews like Tyl from Innerfidelity. Perhaps a weekly roundup podcast as well, no one is addressing this niche properly. :-D

    Today's tech is mostly a rehash of smartphone press releases and social networking news, just obscene.

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  34. "EU hearing protection regulations" Poor Europeans living in the uber nanny state. Creepy overbearing big brother.

    You should try a pair of KRK6400s. Aside from the uncomfortable headband (I have to shift it forward and back every few minutes), very extended, reasonably flat, and lower distortion than the other headphones above. Slightly lacking mid-bass kick and a bit forward in the upper mids, but otherwise very reference. It measures as low or lower (I think) distortion and significantly better bass sustain than the Denon.

    I am still amazed at how much the 80ohm Sennheiser HD25 changes when paired with the Fiio E7. Maybe even darker and too much bass authority than I prefer! Mine is more closed and isolating than normal, so that could be part of it.

    How does the Sony V6 sound change with better amplification? Seems like the 7506's more midrange balance might be a better match for amping if it adds massive, tight bass control. Sony bass distortion performance on innerfidelity's graphs is surprisingly bad compared to the KRK, Ortofon O-One (which I have in storage), and the HD280. Especially considering how Rat Sound discovered an issue with the driver housing on the HD280 resonating severely. V6 still measures worse!

    You're right about the HD280's touches of midrange murk here and there, though. Something inconsistent going on there, not to mention a lack of precision in the highs and some fizz. I really think there's some potential in that driver. Bass is so tuneful and deep on it without being exaggerated.

    I hope innerfidelity, you, or some other reputable site gets their hands on the DT990 Pro. Headphoneinfo.com and that Japanese reviewer guy both strongly recommend it. I'm very interested to see some in-depth comparisons and measurements between that one and the DT880-600. Most people seem to say the 990 Pro has a similar balance to the 770, and yet it gets two strong recommends but is panned on you-know-where. Then there's the AKG and the HD580-650 to consider. Too many choices, indeed! You should see me near the cheese in the grocery store!

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  35. Very useful review. I am trying to decide to get the 80 or 250 ohm version, mainly for listening music, on a mp3 player. I am a bass fan.

    ***My main concern is sound quality***
    I just wonder if I should get the 250 ohm version + an amp XM4 http://www.practicaldevices.com/, or the 80 ohm version, with or without an amp.

    I always wonder even if the 80 ohm version will give better sound with an amp???

    Why xm4, not too expensive (although is already streching to my upper limit). See http://www.head-fi.org/t/214588/review-portable-amp-roundup-56-portable-amps-reviewed-and-compared-final-update-12-20-10-added-rsa-sr-71b

    Wonder how Fii compares with xm4. Any idea? The Fii seems much cheaper (cost is always a factor in the decision making).

    Also, wonder if you know a good portable mp3 player that is not too costly? Some say ipod is good, some sites just say they are horrible.

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  36. I compare the Sansa Clip+ to the iPod Touch 3G and both measure very well--better in most ways than the more highly regarded Cowon player I tested. I'll soon be testing the Clip Zip as well.

    I would probably choose a FiiO over the XM4 as I've tested a few FiiOs and they've been at least decent. I've not tested the XM4.

    I'm really happy with the Pro 80's. They're not only easier to drive, they're also cheaper and more rugged than the 250 ohm "home" version. They get fairly loud with just my iPod Touch or Clip. Within the volume range of either, there's no benefit to adding an amp as both players have a low enough output impedance. So the only thing an amp gets you is more volume.

    So, if you purely want my opinion, I'd start with just the Pro-80's and a Clip Zip (or plus), iPod Nano, or iPod Touch and see if they play loud enough. If not, you can add an amp. My E6 and E11 reviews will be coming shortly.

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  37. Hi NwAvGuy,

    This is a phenomenal review, far more detailed and useful than any other info I've been able to find, so thank you! I'm leaning toward purchasing the DT770 but I was hoping you could be kind enough to answer some questions I had specific to my situation. First some background:

    I recently bought an iPad 2 to replace my iPhone 3GS, and I intend to listen to music exclusively through that. (Maybe once in a while I'll plug the headphones into my Onkyo receiver at home.) The music I listen to ranges from classical to mainstream pop/rock to vocalist to show tunes. I ripped most of my tracks in AAC 128 format. Although, once Apple's iTunes Match service starts, I intend to use that to upgrade everything to AAC 256.

    Currently I have a 7-year-old Sennheiser HD 497 which I think is an OK -- not great -- headphone, but since it's an open design the sound leakage is obviously no good in an office environment or public transit.

    So, what I'm looking for now is a major upgrade in sound quality, combined with a closed design so I won't disturb anyone, combined with something so comfortable that I can wear it for at least a couple hours at a stretch. After reading a lot of info and reviews, I've narrowed my choices to Audio Technica's M50 and the DT770.

    Now, the questions!

    1 - How would you compare the sound leakage of the M50 with the DT770? If there were people sitting 3 feet away in a quiet office, would they hear my music at moderate volume? What about someone sitting next to me on a bus or airplane?

    2 - How well do the M50 and DT770 seal out surrounding noise? I guess my main concern is that if I'm wearing the headphones on a bus, I won't need to blast the volume. I know these are not noise-cancelling headphones, but I'm hoping since they are closed and circumaural that will at least help with this problem?

    3 - Do you agree that in my case, the 32 ohm version of the DT770 is best? This will give me the best possible sound quality given my source material and the iPad? And it's not worth it to bother with an amp?

    4 - Do you think I will notice a significant increase in sound quality with either of these headphones, given that the source material is AAC 128/256 rather than lossless? Or is it overkill?

    5 - Finally, I was thinking about getting one of those iPhone adapters that I could plug into the headphone so I could control the volume more easily. (Also, I could use the iPad as an Internet phone, so the adapter would give me a mic.) My question is, do both of these headphones have the 3.5mm plug? And if so, does using these adapters result in any loss of sound quality?

    I really appreciate your time and advice. Thanks!

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  38. Jonathan, glad you liked the review. Some answers:

    I don't own the AT M50, I just tried them out. So I'm not the best person to ask for detailed comparisons with the DT770. For me the 770 is substantially more comfortable for multi-hour listening and the M50 isn't. But comfort is also head and ear dependent.

    For isolation you might check the InnerFidelity and/or HeadRoom write ups. HeadRoom's isolation graphs are not 100% reliable but they might help. I suspect the M50 and 770 are similar. I doubt leakage will be a problem with either unless you listen really loud in a very quiet environment.

    Both have 3.5mm plugs, I'm not sure about the iPhone adapters and if they cause any problems. Extra plugs can cause noise with movement, degrade crosstalk, etc. But it might be fine.

    Yes I'd get the 32 ohm DT770 although the Pro 80's are more rugged, cheaper, and might be loud enough without an amp depending on how loud you like to listen. I use mine with my iPad, iPod Touch, and Clip+ both with and without an amp. Most of the time I'm happy without an amp but there are times when they don't get loud enough. That's especially true with wide dynamic range music like classical. See my More Power? article.

    The 128 AAC issue has been endlessly debated but ultimately it's a personal thing. I would suggest a blind test with an especially well recorded track in both formats and see if you can tell them apart. You can do that yourself using Foobar 2000 with the ABX plugin. They need to be level matched and from the same source.

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  39. Thanks for the awesome review!

    I'm new to high end audio and I've got a a few questions...

    What benefits does the DT770 gain through having higher ohms? All i could tell from your review was that the 32ohm version handles better from lower quality sources.

    I will using my iPod touch 4G as well as my PC for most of my listening - Is a dedicated soundcard better in any way than an amp?

    If i was to get a Fiio E7 or E11 would there be any reason to still get the 32 ohm version?

    Also, I wonder if you have had any experience with trance/house music on these headphones as that would be what I will be listening to most and wonder if they are a good suit.

    Thanks for any feedback.

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  40. NwAvGuy, thanks for your response! I wound up going to our local Guitar Center and trying out 5 or 6 different headphones (including the Audio Technica M50) and the DT770 was by far the most comfortable. Also maybe my ears aren't sensitive enough, but those two sounded almost identical -- I couldn't detect much difference. They both sound terrific. After using the DT770 for the last few days I'm really happy with them. The only issue was that they didn't have the 32 ohm version, so I went with the 80 ohm like yours. (It's strange that the 32 ohm version is so much more expensive on Amazon, I wonder why?)

    I think your assessment is spot-on. Using an iPad I find you do need to turn the volume up to about 50-70% of maximum for most tracks in order to get a decent sound. For movies and classical, I find 90-100% is just barely enough. I read your review on the Fiio E5 and for $20 that seems like a reasonable solution...unless you can think of something better?

    Also I've been able to wear them at work and even with the music blasting pretty good, nobody else can hear a thing. And on the bus, they isolate you fairly well...maybe noise cancelling headphones would do slightly better, but then you get the trade off in sound quality.

    One interesting thing I noticed, in iTunes I had set most of my tracks with the "Rock" equalizer setting. With my previous headphones, this sounded OK. With the DT770, it sounds pretty bad -- muddy and unnatural. I found that turning off the equalizer entirely gave the best results. Now it sounds warm and clear.

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  41. @Jonathan thanks for your comments! The Pro 80 is cheaper because it's a more rugged, and less fancy, version designed for pro use rather than home use. The 32 ohm version has nicer earcups, a nicer handband, etc. And yes, you likely don't want any serious EQ (or at least not any deep bass boost) with the DT770.

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  42. Thank you for your review. Based on many reviews, I had originally purchased Grado SR80 and iGrado headphones. I loved the sound of the iGrado but found them uncomfortable after only 30 minutes of use! I did not like the sound of the SR80s and I found them uncomfortable. I returned both. I went to a local store to try the Grado SR60s, I didn't like them any better than the SR80s. While in the store I tried a number of Beyerdynamics and ended up purchasing DTX910s, which I think sound very good. I then ordered a pair of Beyerdynamics DT770 Pro 80s and just received them today. I've been listening to music all day and I'm very impressed with them and will be keeping them. I'm using them with an iPod Touch 4G and there is plenty of volume; I'm currently listening to Diana Krall music at about 60% volume and it sounds great.

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  43. @Malcom, thanks for your comments. I don't find any of the Grados I've tried very comfortable either. They use a very crude mechanical design and sit more on the ear rather than over it. Headphones are not much use if they're not comfortable enough to wear for any length of time. Beyer makes some of the most comfortable headphones I know of.

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  44. Very good review! But why don`t you use asio? I`ve Heard somewhere that windows forces all the sound to 16 bit 44.1khz? am I right?
    I always use asio. That way I can be really sure that I`m listening true 24 bit with my laptop wich has a 192 khz 24 bit soundcard

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  45. Windows XP, Vista and Win 7 do NOT force all audio to 16/44. I'm not sure where you heard that, but it's not true.

    ASIO is mostly for recording not listening. The main benefit for ASIO is usually decreased latency--the time difference between what's being played and what's being recorded. For musicians laying down a multi-track recording, latency is important. For audiophiles just listening to music (and not recording at the same time) it doesn't matter at all.

    If anything, because they're optimized for low latency, ASIO drivers often perform worse for playback than the native Windows sound drivers. ASIO typically uses much small buffers which often results in more glitches, lost bits, etc.

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  46. Hello,
    A bit late commentary, but would you say then that a 250ohm version would be better than the 80 for an intern soundcard like the xonar DX (with unknown -to me- output impedance but probably not much less than 100ohm) ? Except the fact that the 250ohm would probably not be loud enough ...
    I am struggling to decide which version would be the best for my configuration and my tastes :D

    I listen mostly rock music of all sort (from oldies to metal through progressive) but also all sort of music, I still can't understand if basses are really overwhelming or not by reading reviews, but I like bass anyway (without beeing a true basshead, I think).
    I also search for a really comfy headphone and a good soundstage for games, so maybe the 770 premium/edition/2005 would suit better to me but again I can't find a way to determinate if premium editions would really change the sound quality ;(
    Maybe in the future I'll buy a little cheap amp but if I can do without for now..

    ps : Anyway great article, thanks for this exhaustive review
    And sorry for my approximative english :p

    ReplyDelete
  47. Hi, i got these headphones after reading your review. can you please suggest a portable amp that can drive them. I generally use them with my laptop and sometimes with the ipod. I have tried these headphones without the amp and i am not fully happy with the sound.

    ReplyDelete
  48. @foudelou, I have no idea about the Xonar DX, only the ST tested by Stereophile. I also only own the Pro 80's and have only heard a few other Beyers relatively briefly so I can't really make detailed comparisons.

    @anon, any of the amps I've reviewed should get loud enough with the Pro 80. It really depends on your budget. The FiiO E11 might be a good one to look at first. If you want to spend more, I'd suggest an O2.

    ReplyDelete
  49. Thank you for replying quickly....my budget for the amp is 100$. Also is the Fiio E7 better than E11? How much does the O2 amp cost?

    ReplyDelete
  50. The O2 is probably over your budget unless China starts making them. The price fully assembled is around $150. See: O2 Amplifier and O2 Resources

    The E11 is better for 80 ohm headphones (like the Pro 80) than the E7 by a significant margin. But it's apples and oranges. The E11 is just an amp, while the E7 is also a DAC. If you want a heapdhone DAC, consider the E10 which more or less replaces and is a big (and cheaper) upgrade over the older E7.

    ReplyDelete
  51. Thank you very much for all the information. I will probably get the E11.Also according to most of the reviews of BAYERDYNAMIC DT770 PRO 80 it has good bass. However when i used it i was not happy with the bass. Will the amp help improving the bass? I have been using MONSTER TURBINE PRO COPPER earphones for a long time now. I got the pro 80 hoping that it would sound as good as the turbines. Are the pro 80's any better than the turbine copper?(atleast in bass)

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  52. I've never heard the Turbines as I no longer buy any Monster products. I don't agree with their business philosophy. They do have a reputation for having really excessive bass.

    The Pro 80's have a lot of very deep bass but not the boomy, bloated, sort of bass you might be used to. An amp may help. It sounds like you want them louder anyway, so get an E11. It also has Bass EQ that you might like. Enjoy.

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  53. According to your review PRO 80 will sound better with a low impedance source.Can you please explain what a low impedance source is with example if you can.Is FIIO E11 a low impedance source?
    Sorry for troubling you but i am new in this area and trying to understand what it is. I just want my pro 80 headphones to sound good with good clarity.
    Thank you once again.

    ReplyDelete
  54. Also i use my headphones with a laptop...so will a E10 DAC be a better option than E11 amp?

    ReplyDelete
  55. If you read my E11 review it has a very low output impedance. See my February articles on impedance if you have further questions. The E11 is a fairly good match for the Pro 80.

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  56. Hi!

    Been reading your informative article and just to say I am listening to my new 770 Pro/250s as I write this and am comparing them using my Audigy 2 breakout box on the PC and on my iMac with a Fiio E10 DAC. They are, as you say, much more comfortable than the M50s which I have now sent back as they hurt my ears!
    I also have a pair of Grado 225s which are about 3 years old and they now sound overbright compared to the Beyers. I do prefer the open back sound and as someone else said, the Beyers don't have the boxy bass that many closed cans have.
    The problem is there is always something better out there if you have the time and money to hunt them down.

    Greetings from London

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  57. Hi, thanks a lot for your review, it helps me a lot. I just bought dt 770 pro-80 2 days ago. I'm a newbie in headphone knowledge, i really hope that you can help me to give some suggestions for what i should do to burn in my dt770 correctly to get good sound. How long should i do it? what kind of music do i need to use? Can i just use all kinds of music randomly or i need to use white noise/ pink noise (honestly i also don't know about those noise *sigh).
    I read some articles which makes me more confused, because different article gives different ways to burn in. one says need to use those noise...the other one says that we can use all kinds of music, and some articles say no need to burn in, just use it in ordinary way, coz burn in effect is just psychological effect. Please help me. Thanks

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  58. Headphone "burn-in" is generally fairly minor. I've run some burn-in tests as has Tyll at InnerFidelity. The differences between brand new headphones before and after burn-in are fairly minor. Most of the changes people think they hear are entirely psychological as you suggest. Human hearing is easily influenced by many other factors. See my Subjective vs Objective article.

    For anyone who just wants to be safe, using music is fine but it should have some significant bass content and be played at fairly loud (but still realistic and listenable) levels for at least 8+ hours.

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  59. Amazing article; thanks a bunch!

    I've been an exclusive 7506/V6 user for 9+ years (I have both) and I recently listened to the 80ohm 770 along with the ATH-M50 driven by an iPhone. The M50 had an upper bass peak that was kinda obnoxious and a clamping force that was far too high. I wonder if the iPhone's reasonably low output impedance isn't low enough to keep the M50 clean. The 80ohm 770 seemed very flat and honest but yes, there wasn't enough voltage swing to drive this can to a decent output level.

    The comments about the earcups are interesting. I guess I have small ears because I can wear the 7506 all day long. The DT-250 pad upgrade made them even better.

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  60. im about to buy these HP with Asus Xonar Essence STX but im a little worried about the internal headphone amp and its power i think its lots of performance for the price (DAX/amp both in one unit) but still if it cant give the 770 80 ohm justice enough i have to reconsider buying external DAC/amp instead.

    its only for desktop use and no portable use at all

    i dont want the bass to be weaker and with a lesser boomy impact than my current Logitech G35 usb headset.
    you think this asus soundcard would be enough? or do i rly have to buy more serious expensive stuff like your benchmark DAC1 to be able to hear the full potential from the 770s?

    thx again for a wery detailed review!

    ReplyDelete
    Replies
    1. The STX's head amp uses the same output chip as the Fiio E9 so it got got plenty of power. The output impedance just make the cut off for the 1/8th rule so the bass should be too loose.

      Delete
  61. Hello,

    I've been reading this blog with great interest for a few months now and I must say that I have been incredibly impressed by the level objectivity and empirical zeal with which you present your findings; It's certainly a refreshing approach compared to some other sites. I have been reading the above review with great interest as I have am looking for a headphone which is comfortable enough to listen to for many hours on end without either physical or aural fatigue and the over ear, as opposed to on ear design of the DT770 certainly seems to suit this requirement. I currently have a pair of Grado SR80i and whilst I do like the sound, they quickly become very fatiguing. I have borrowed the earlier DT220 and found them comfortable so I have no doubt these will be too. I do have a question however; Since the majority of my listening is done on either an iPhone or iPod, I recently purchased the Fostex HP-P1 DAC/Amp and wondering as which would be the correct model of this headphone to go for in combination with this device. The manufacturer specifies 80mw into 32ohms. As it appears that the 32ohm version could be driven with ease, so i wonder what would be gained from opting for one of the higher impedance models. Ear damaging volume isn't a requirement, but it would be nice some reserve for when the occasion demands it. I would be so grateful of any advice you could offer on this subject, also thanks for great service you're doing for the hobby with everything you publish here.

    ReplyDelete
  62. I use my DT770 Pro 80's relatively often with no amp on my iPod Touch 3G. They're fine Un-amplified on the Touch if you're not after "live" listening volumes. When I want more volume, I add an O2 amp.

    I'm not familiar with your Fostex amp so I can't really comment. I do agree the 32 ohm home version of the DT770 should be fine (likely even without an amp).

    Just to be clear, in terms of "fatigue" the DT770 is very comfortable physically but in terms of "sonic fatigue" I'd say it's only average. As mentioned in the review the high frequency performance could use some improvement. Compared to many headphones the DT770 Pro 80 has less fatigue, but compared to say my Sennheiser HD650's the DT770 sounds a bit harsh--especially on poorly recorded/mixed tracks.

    Still, even with less than ideal HF performance, the DT770 can be a lot of fun with the right music. While some might argue the deep bass is a bit too much, it's a matter of personal taste. More than any headphone I own the DT770 can really make you take notice on tracks with nearly subsonic deep bass.

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    Replies
    1. Wow, thanks for the swift response.

      Fostex suggest a minimum load of 16 ohms here: http://www.fostexinternational.com/docs/products/HP-P1.shtml#3

      It was certainly more the physical aspects of the Grado's that find fatiguing. so the 770s are still looking good.

      I had wondered if the Sennheiser 650s may be to hard to drive, sadly I've yet taken delivery of the amp (it's on order, but I did try it in a local store here in the UK). If can find a good deal on the 80 ohm version (I wonder if the 250ohm version may be touch and go ?!) of the DT770 I will probably give them a go.

      Once again, many thanks for the help.

      Delete
  63. Hi NwAvGuy,
    First time I've read about you and in one evening, change my perception about psychoacoustics! Talent like yours is very much appreciated!

    I do have a quick question if you don't mind. I bought a DT770 80 ohm and was planning to make the O2 amp. If I'm right, the gain settings are adjustable. Would you mind recommending the best setting given this headphone? I know you are inundated with requests for combinations but this is related to two articles you wrote :-)

    Thanks a bunch!
    John Nibor

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    Replies
    1. Without knowing your source it's impossible to answer your question. There's a 4X or 5X difference in gain requirements between say using an iPod dock output vs using a home CD player. In general the 2.5X standard low gain setting should work fairly well with the DT770-80 with most sources. For more see: All About Gain

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    2. Thank You for taking time. Yes I forgot about that. I was going to use on my old Rega Planet. Best Regards

      Delete
    3. BTW - the reason I found your blog was when I first tried on the headphones, I noticed the vocals were nasal on the track I was listening to. I Googled "DT770 Nasal" and found your site... So, spot on with the review :-)

      Delete
  64. Hi first of all i want to say that your reviews are effin amazing, and it really intimidated me. But I hope it is ok to ask you some newbie questions.

    I would like to know if the DT770 Pro 80 can be driven by Fiio E11? I did not quite understand what it means by 'amp with low output impedance'? How do i find out if an amp has low or high? The specs seems confusing to me. I am very new to this

    I am actually looking to get the E11 and pair with a headphone like Sennheiser HD555 or something within my budget. If i can pick on your brain, do you think it is good mix? The reason i picked 11 is because i read that it enhances bass, which seems good for me. And also because of my limited budget.

    I generally like the "fun" type of headphones i.e. ATH-M50. But despite my preference for "fun" i also want a different headphone that will serve well playing the holographic audio (Naturespace) which i got over the iPhone app. The reason why i get into this is because of this app, the nature audios are amazing. Did you try it?

    But i'm debating with myself whether soundstage is what i want considering i want the experience to be 3D experience and as-close-as possible to me, but yet, not too far away from me. I want to feel exactly like the sea waves are crashing ON me and not further from me and the sound of wind and leaves directly above me, not above but further from me (if you get what i mean?). I dont even know if there is such a thing. I tried the DT 880 and found the sea waves crashing further from me, soundstage is great - but thats not what i want. But from what i underrstand, soundstage is what helps the 3D experience? Or did i get this wrong?

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  65. Yes, The E11 is a good match for the DT770-80. I don't know the HD555 specs offhand, but that's probably a decent match as well. The ATH-M50 should work well also. Beware, however, the E11 only runs from its battery so it makes a lousy desktop amp.

    If you're after the best "3D experience" I would look for the most open sounding headphone that meets your other criteria. The DT770 is surprisingly open for a closed back headphone but some open back headphones are even better.

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  66. NwAvGuy

    Great review! I am about to take the plunge into higher end audio and I heard the 770 80 ohms today and loved them. I am going to use them for movies and gaming on my pc. My question is I have a asus xonar dg sound card (headphone amp built in) so should I buy another amp or amp/dac combo? or should the sound card be plenty?

    Thanks again!

    Chris

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  67. Most (all?) Asus audio devices have a 20+ ohm output impedance. Unfortunately that's not a good match for the DT770-80 and will result in boomy poorly controlled bass (see my Feb 2011 amp impedance article). I would suggest an amp even if it's something inexpensive like the FiiO E6 or E11 but beware the E11 can only run from battery power. If you want something that's USB powered the E10 might be a better option. An O2 will work well also.

    ReplyDelete
    Replies
    1. Thank you for replying my earlier post (about 3D and Naturespace). I have a similar question to what Chris is asking.

      I am considering of getting a Creative Sound Blaster: (1) Creative SB X-Fi Go! Pro, or (2) Creative SB Digital Music Premium HD.

      My first 'technical' question that i want to ask is, how do i know if its output impedance is enough to drive a headphone? Say DT770 - 80 or 250 ohm?

      Like-wise, how did you know that ASUS have 20+ ohm output impedance? I checked Creative's website and their specs had no info that tells me anything about output impedance.

      Second question in on sound quality perspective, which would be better? ASUS or Creative?

      Trying to get the best out of my laptop SQ, I thought of going something like this:

      (A) Laptop --> *(B) USB Sound Card --> (C) Amplifier+DAC --> (D) Headphone

      Which leads to my third question - Ss it possible or necessary to add *(B) in between what normally people do, or would that overdo it?

      My concern, as you pointed out earlier - that the USB Sound Card does not have enough output impedance to drive those headphones. But the reason why i thought of adding it is because the EQ Software features that Creative provides. Would that be fine?

      Would appreciate your expert opinion.

      Thanks!

      Sincerely, ET

      Delete
    2. I've just read the Stereophile review and it says this about Xonar Essence ST and STX (which also have the same amp as Xonar Xense: Texas Instruments 6120A2):

      'The line output impedance was a moderately low 99 ohms at all frequencies; the headphone output impedance was 10.7 ohms at all frequencies and settings. All the outputs preserved absolute polarity; ie, were non-inverting'. Source: http://www.stereophile.com/content/asus-xonar-essence-ststx-soundcards-measurements

      So, we can conclude that DT 770 perfectly matches this kind of amp. The question is: has Xonar DG the same output impedance as the amp used on Essence/Xense? I don't know. But I read several people guessing it has something around 10 ohms. It seems that it doesn't have the same power output as the 6120A2, once the manual says DG can only be used with headphones up to 150 ohms.

      Delete
    3. Without testing a DG it's hard to know for sure. But considering the U3 I tested has an even higher output impedance it seems it might be a general flaw with Asus Xonar sound devices in general.

      I wouldn't say a 10 ohm output impedance is a perfect match for the DT770-80. It's right on the edge of being unacceptable. As mentioned in the article, the DT770-80 already has too much bass for many tastes. A higher output impedance boosts the bass further and makes it more "boomy" and less controlled. So ideally you want a source as close to zero ohms as possible unless you like boomy exaggerated bass.

      For more on why lower impedance outputs are better, see:

      Output Impedance

      and

      Sonic Advantages of Low Impedance Headphone Amps

      To the previous question from Anon, you don't need or want an internal soundcard if you're using a USB headphone DAC (which is a DAC+amp). You just plug it into a USB port and you're good to go. Using USB is better than an S/PDIF digital output for a variety of reasons.

      Delete
    4. Hmmm... I said 'perfectly match' because of your article about impedance that states the optimal value for an output impedance to be at least 1/8 of the load impedance (i.e. headphones).

      BTW, amazing the other article from BenchmarkMedia. The THD is really HUGE if we use a high impedance output with a low impedance headphone. Almost unbelievable.

      Delete
    5. I should double check where I reference the "1/8th rule" but I generally have said the output impedance needs to be less than 1/8th the headphone impedance--not equal to. But I could see how someone might get that confused.

      The nice thing about measurements is they're easily verified by others. So Benchmark (or anyone similar including me) would be taking a big credibility risk to intentionally publish erroneous measurements--especially when they're the basis for an entire article. It's like Ford saying the Mustang GT does zero to sixty in 5 seconds. If they're wrong they won't get away with it for long as as it's easy enough for others to verify.

      But when someone claims a headphone amp sounds "dark" or "open" that's much harder to verify or dispute as it's subject to individual preferences, use of vocabulary, etc. That's one reason why 95% of audio reviews are purely subjective. It gives the reviewer much more freedom to claim whatever they want with relative impunity.

      Delete
    6. @Delerue, here is a table of the main parameters of the headphone outputs of most Xonar products from various sources. It is not complete, but maybe the information below is still useful:
      - Xonar U3: 23.6 Ω (source: NwAvGuy article), DRV601 (not sure)
      - Xonar DG/DGX: ~10 Ω, DRV601 (my guess based on photos of the board, may be incorrect)
      - Xonar DS/DSX: unknown, NE5532/NJM5532
      - Xonar D1/DX: ~100 Ω, 220 uF, NJM5532, ~1.94 Vrms maximum output (my own measurements)
      - Xonar D2/D2X: unknown, but most likely similar to the D1/DX
      - Xonar Essence ST/STX: 10.7 Ω (measured by Stereophile), TPA6120A2, fully DC coupled, ~28 mV DC offset on the card I tested
      - Xonar Essence One: 10.2 Ω (measured by DMarasovic at Head-Fi), LME49720+LME49600

      The Benchmark article is of course very unlikely to contain incorrect information. You need to take into account, however, that they tested at a rather high SPL (sine wave at 106 dB), where the headphone drivers themselves likely had even much higher distortion at low frequencies than what was measured on the high impedance amplifier output. It would have been more fair to present the data as a dB increase of THD and IMD in the acoustic output relative to a near zero impedance source.

      Delete
  68. There are a pair of circumaural headphones by an Asian OEM called Superlux that come fairly close to Beyer's DT990, but cost only about 1/10 as much. This here is Superlux' own frequency response chart: http://goo.gl/KganB and HeadRoom's chart seems to back that up: http://goo.gl/m0cf6 - However one of the main differences is that these headphones have only 50-70 Ohm impedance (Headroom writes @1kHz: 56 Ohms).

    So my question now is what amp to use for driving these given that the pc output has 10 Ohm impedance (that damned Asus Xonar). Changing the sound card is not really an option, since the main purchasing reason for the card was its Dolby Headphone feature for Gaming, and the reason I'm looking at these headphones is because people claim that open-back circumaurals create a "wide soundstage" that works greatly together with the simulated surround by Dolby Headphone. Weirdly enough, other "gaming-headphones" and "gaming-headsets" that Asus' Xonars are aimed at have low impedances too (32 Ohm mostly). So basically an amp with suitable impedance is my only option here right?

    I had an O2, and enjoyed it, but gave it away again, as what I really wanted was the ODA to begin with. However it would be great to have something in the meantime, for about 50 EUR (65 USD?) that will properly drive circumarual headphones/headsets with 30 - 70 Ohm and won't have too much noise/distortion.

    Will a Fiio E5 provide enough power? Or will it degrade the signal too much? The Xonar Essence STX does have a bundled amp, so it would be possible to input a "pre-amplified" signal into the E5 (or any other amp) but since the E5 doesn't have any gain setting I'm afraid that I'd probably damage it (and the headphones along the way) by doing this.

    Do you have any recomendations what I could use? Or by how much would I have to go up with the price to get something decent?


    I am sorry to bother you with this stupid Xonar topic again, as I can see that there have already been endless questions about it on various articles of your blog, but they were mostly about sensitive in-ears, not full-sized cans with low impedance .. so hopefully this question will provide at least some new information.


    Thank you .. for doing all this! :)

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  69. @Grunty, do your DT990 clones really sound that bad with the Xonar as is? They're close to being borderline OK with a 10 ohm output impedance. If what you really want is an ODA I would just use them direct from the Xonar until the ODA is available.

    Without knowing the sensitivity of your headphones I don't know if the E5 would have enough power. See my More Power article and E5 review to try and figure that out if you're still interested in one.

    ReplyDelete
  70. To be perfectly honest, my Xonar is still in the mail and I haven't quite decided on the headphones yet - so i can't tell you wether it sounds bad, or wether I can notice the sound degradation. Other than the DT990 clone, there is a "gamer-"headset (http://goo.gl/EkG04 - 32 Ohm, 102dB Sensitivity) that seems to vaguely resemble the Sennheiser HD 650's (http://goo.gl/ehx9l) frequency response.

    The advertised sensitivity for the DT990 clone is 98dB/mW (http://goo.gl/110As - you can change the language in the dropdown on the top right) wich would work out to a peak SPL of about 112dB according to your article .. which should be enough for "normal" usage, right?

    (Fiio E5 voltage @15 Ohm was 1.27, so P=1.27*1.27/56=28.8mW and PeakSPL=98+10*LOG10(P)=112.6dB)

    So I guess i'll give the E5 a try and report back when I have everything.


    Btw, what do you think about these "frequency response" charts, how reliable/meaningful are they actually? I know you said it varies from HATS to HATS and person to person, but the measurements for the different headphone modells seem to be consistent enough between the different measuring/benchmarking organizations (HeadRoom, iHeadphones, innerfidelity).
    But on the other hand if the (measured) frequency responses really are what set different headphones appart, why would manufacturers willingly distort the output? Why do we enjoy a "v-shaped" reponse in a headphone but demand a strictly flat one from our dac/amp? Considering this, shouldn't AKG's K701 be the "gold standard" for headphones, and shouldn't newer models try to "flatten out" the "curves", instead of introducing new ones?
    I read your article about the HD650s and their reduced listening fatigue, regarding "what you don't hear" and bad recordings, but I wonder if a headphone really is the best place to solve this issue. Wouldn't a software filter be able to achieve the same result much more acurately, and in a "lossless" fashion (meaning that you could just turn the filter on or off, or apply different filters to different tracks depending on how bad they are)?
    You said you couldn't quite recreate the HD650's effect with an equalizer .. but is there anything that prevents much more fine-grained equalizers that operate directly on the digital data of music files?

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  71. @Grunty, some good questions...

    For the reasons mentioned in my new What We Hear article I think digital EQ and the headphones are the best places to alter the sound to a person's individual tastes. Both are valid methods. If you're bass head it's perfectly valid to buy bass heavy headphones.

    You asked why all manufacturers don't strive for flat response and the simple answer is such headphones, like the AKG K701 and Etymotics, only appeal to a limited market. Some might expect me as "Mr Objective" to favor such headphones but I don't. I bought the less accurate HD650 over the K701 and I rarely listen to my Etymotics.

    A lot of people listen with portable devices and their EQ options are more limited--sometimes severely so. So the headphones themselves are often a better way to get the sound you like. If you only use a PC as your source you have more EQ flexibility but that still doesn't mean you make the $25 HD201 sound like a $1500 HD800. There's more to it than just frequency response.

    I did use a fairly "fine grained" digital EQ with my experiments with the HD650. If you look at the HD650 measurements by others online, you'll find they have unusually low distortion. So one might have better luck trying to EQ the HD650 to sound like the Denon D2000 rather than the other way around. Because no amount of EQ will alter the inherent distortion characteristics of the D2000 to match the HD650's.

    There's the nature of distortion in headphones (i.e. 2nd harmonic vs 3rd harmonic vs IMD, etc.). This is unique to the driver and cannot be significantly changed by altering the signal. Standing waves are created within the earcup and within the headphone housing. These create a very complex comb filtering effect that would be difficult to recreate reliably with any amount of EQ.

    ReplyDelete
  72. @Grunty

    There's a lot more to a headphone's sound than just the FR.

    My main full size headphone right now are a modded pair of Fostex T50RPs. They don't have the smoothest frequency response or the lowest distortion but they do have very clean decay (as shown in CSD/waterfall plots) without any sharp ringing at specific frequencies.

    Any headphone is a compromise so you'll have to pick one based on what problems bother you and which one don't.

    ReplyDelete
  73. Hi, NwAvGuy!

    Hopefully, I may soon have the opportunity to purchase a set of new cans as an upgrade to my present Grado SR-60s. My electronics will remain an iPod Touch 4G and O2. As I've gratefully commented in previous posts you've kindly published, I believe that I heard, for the first time in nearly forty years of listening, sounds essentially indistinguishable from live music upon adding the O2 not long ago.

    As such, I was considering Grado SR-125i's as a treat for myself . However, I do love the "thwack" of sharp, deep, clean bass (and highly kinetic, intricate music) and am intrigued by your comments regarding the Beyer DT-770 Pro 80s.

    If I may ask your opinion...? I am thrilled upon detecting fine, subtle details in musical passages in addition to my fetish as described above. Do the Beyers sacrifice any acoustic "resolving power" in order to provide those subsonics? I ask not just because my current SR-60s have proven surprisingly revealing with the O2 and I would find myself missing that characteristic if it were to disappear, but also because you make reference to a somewhat "nasal" and withdrawn midrange (where most music resides).

    I understand the difference between opinion and fact, so please fear not, sir! I also am aware that I am likely chasing after rapidly diminishing returns regardless of which set of cans I 'spring' for.

    Jonathan

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    Replies
    1. That's a really hard question to answer--especially when I don't own any Grado headphones. I would suggest others who do (or have) owned both headphones are in a better position to answer your question than I am.

      I can say the DT770 is far more comfortable than any Grado headphone I've ever tried and has better deep bass. But through the midrange and highs, it will come down to personal preferences. I would expect many to prefer the Grado's sound but the DT770 also has plenty of fans.

      Personally I think the under $100 Grados are a bargain in terms of sound quality. The more expensive Grados I've heard have not been as impressive relative to their price. And they're all kind of clunky and get uncomfortable (to my ears/head) for longer listening.

      I would suggest you either try to arrange a listen for yourself of any new headphone (including the SR-125) or at least buy from somewhere with a generous return policy. But you might want to gather other input first.

      Delete
  74. Thank you for your kind response, NwAvGuy! I would invite opinions from any of my fellow audiophiles (is that still considered an appropriate term)?

    I was wondering if during your listening sessions with the Beyers, were you ever struck by the perception of inadequacy (a blurring of sharp acoustic edges) or a dearth of "resolving power?" I admit that I don't know what terminology to use to express the ability of an audio system using headphones as terminal transducers to reveal extremely subtle detail (likeness to live music) in musical passages (typically at the very low end of the dynamic range)?

    Please excuse me for my shortcomings of expression.

    Jonathan

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    1. That kind of thing is relative. Going with headphones I've owned I'd say that the 770 Pro 80s lack "detail" compared to the HD650s or my modded T50RPs but would exceed the SR80 and XB700.

      Of course defining "detail" is pretty hard and involves lots of different properties of a headphone. Frequency response affects relative volume and psychoacoustic masking, the driver's decay to silence and harmonic distortion need to be considered as well.

      Also, the Pro 80 and the SR60 have such different frequency responses that you'll really want to try before you buy or order from a place with a good return policy unless you have some other points of comparison.

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  75. Thank you, NewAvGuy and Maverickronin,

    I now agree and perhaps understand that the selection of terminal transducers is essentially a subjective process given the variability of the human acoustic system. The individual variability that characterizes us as a species results in an astounding degree of non-uniformity in perception from person to person. Probability is the culprit, whether examining the conceptually similar marvels of snowflakes, fingerprints, retinal architecture or people. Reality is a crapshoot.

    Given budgetary constraints, I believe I will give a try to privately selling my ER-4Ps (presumably via Ebay or a similar internet 'vehicle') to finance the purchase of (most likely) the Beyers.

    Perhaps I am reading between NwAvGuy's lines, but I sense a hint that higher grade Grados (SR125i) will provide sounds that differ from that produced by my SR-60s in subtle and miniscule ways only (again, diminishing returns), whereas DT770 Pro 80s may offer a fundamentally distinct experience.

    I guess I'm trying to say that I'd rather obtain two good views from significantly differing vantage points than nearly identical views which differ by only one or two degrees. As long as neither set of 'phones is flawed by obvious distortion, the notion of making a choice that is flatly right or wrong perhaps does not apply. That was the concern about which I was trying to inquire regarding the Beyers in my earlier posts.

    I will heed your respective wise words to either attempt to arrange listening tests or locate an outlet with a reasonable return policy.

    Thank you both!

    Jonathan

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  76. It took a while till I had everything together, and sufficient time to listen to it, due to the holidays.

    I am surprised how little difference there was when listening to the Xonar's headphone output directly compared to listening through the E5. I even had a chance to try it with the O2 again - but the result was mostly the same. I even tried 32-Ohm cans (the earlier mentioned gaming headset, and Superlux' HD662 that are supposed to be DT770 clones) and 16 ohm in-ears (Sony MDR-EX35, 100dB/mW), but again the same. In fact I'm not even sure if I really heard any difference or just imagined it – since the time involved in switching things was clearly above the 0.2 seconds guideline. The only clearly audible difference was the noise by the E5 when no music was playing. This probably is why the Xonars or FiiO’s E9 can get away with 10 Ohm output impedance, without too many customers crying out.

    I also was surprised by how inaudible the E5's channel imbalance (that 4dB difference you measured, with bass-EQ deactivated) was, which was my primary concern for the E5.

    I'll still be going for the ODA+ODAC when it's out, mostly for the "peace of mind" you've mentioned in your articles - but this experience does still put things into a new perspective. Judging from your article, and especially from Benchmark's paper, where they made a case for having a damping factor of not just 8 or 10, but a of a few thousand, I certainly expected something more clearly audible.

    In fact maybe Benchmark's papers need to be looked at more cautiously in general. When you look at their Jitter-Article ("Jitter and Its Effects"), rather going for the threshold of audibility (like you do), they say jitter needs to be 25dB below the A-weighted THD+N rating, because people can pick up tones 25dB below white noise.

    Of course it might not be just my ears that are so insensitive, but also the headphones involved. I am thinking of getting Sennheiser's HD650, since there is an objective case to be made for their low distortion, but I still feel like not knowing enough about headphones for spending that much on them. The essential question here I guess is, other than comfort and the subjective preferences for frequency response, what makes a good headphone? Why are the Grados SR60 so widely regarded as good, but your average no-name headphone at the same price point not? It can't just be the distortions - the SR60 are barely any better than the Sennheiser HD201 in that regard; and the HD800s have more distortion than the HD650.

    Those CSD charts do look interesting, but I don't really see why that would matter. Given a sufficiently low output impedance, the amp should be capable of coercing the headphone's drivers/coils into any position quickly enough and without facing much resistance (what Benchmark demonstrated right?).

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    1. It's good you're doing your own comparisons. What ultimately matters to you is what it sounds like you. That goes for all--headphones included. The HD201 is surprisingly good for the price. In some ways I like them better than the five times more expensive HD280. Sennheiser is sadly rather random with their headphones.

      I think a lot of what makes a good headphone great is how it interacts with the human ear. And that's also something that's only roughly approximated by HATS (simulated head) measurements. Further, as explained in James Johnston's articles, the human auditory system has some rather complex filtering mechanisms that microphones in a plastic head lack. Put simply, once acoustics (sound waves in 3D space) enter the picture measurements can only go so far in predicting the sound.

      By far the most audible output impedance issues are with B.A. IEMs where you can get 10+ dB of frequency response variation as I and others have shown. My test with the DT770 used 120 ohms--the ill conceived IEC standard and close to Beyer's own headphone amp. With 120 ohms you can hear a clear difference in their bass performance. With 10 ohms, as you tried, it's much more subtle.

      Benchmark takes a conservative approach to performance criteria. John Siau's history is in studio gear back in the analog days where a lot of gear was strung together and the effects of noise and distortion were additive. So while one piece of gear's distortion by itself may not have been audible, if you strung six similar pieces of gear together in a chain the sum total could be audible.

      The "tone below the noise floor" argument has some validity when you're listening for a single tone. So it can be applicable under some circumstances. But the masking effects of music, and the fact some jitter is related to the music, make ultra low levels much more difficult to detect. There's more on that and a test you can take yourself (by Ethan Winer in the Myths Video) in my What We Hear article.

      The channel balance problem with my E5 I was likely unique to my sample. I think I commented on that in the review.

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  77. Hello

    I've just received my 770 pros-80. Now, I've connected them directly with my imac. Will there be a remarkable improvement of quality if I add an AMP/DAC like an E17? Or would you even prefer the cheaper E10? Or nothing?

    Do you know how much it is for to skirt the onboard sound with a "cheap" AMP/DAC?

    Thanks for your help!

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  78. One thing the DT770, HD280 and ATH-M50 have in common but the AH-D2000 lacks is that drop around 70-80Hz in the frequency response. I wonder if this is somehow related to the ringing in the 50Hz square wave test chart - by just the looks of it, it doesn't even look like something to be called "ringing" and resembles more of a second attempt at overshooting. Most other headphones here don't have any ringing, but they also don't manage to maintain such a high average level as the DT770. I guess this is what gives the DT770/M50 their trademark-deep-bass?

    To further complicate the differences between the various DT770 versions - I think headroom might have gotten their charts mixed up, since the charts for 600 Ohm DT770 miss both of the features mentioned above that the DT770 with 32/250 Ohm have. And what's more, Tyll's measurements for the 600 ohm version do show them - but he uses 30 and not 50Hz. Sadly I can't find any charts for the 80 Ohm pro version.

    You probably are spot on with your assessment that Beyerdynamic themselves have no idea on what's the "best" solution here and are just trying to sell a product line that will perform similarly across a wide range of usage scenarios - in a 32 ohm variant for mobile use, and in 600 ohm (actually more like 650-750) for use with high-impedance outputs of home-devices.

    With regard to the nasal mids, is there any chance that this is what's actually responsible for the DT770's large soundstage? English is not my primary language, so I'm not familiar with every connotation the word nasal may carry and how to properly use it for sound properties. But when I was listening to the DT770 the word that came into my mind was dry (with regard to vocals mostly). I didn't really object to it though - and if I'm correct in my guess about the soundstage then it might be a worthwhile compromise.

    One more thing - I want to test the sound leakage of the headphones. I don't need a proper measurement, but just a simple by-ear judgment as to how much noise I am exposing the others in the room to. Just leaving the headphones on the desk, and observing how loud it gets, seems to be a poor approach, since the inner part of the ear cup is free to radiate into the room. But I also don't want to put them on another (real person's) head while I'm experimenting with the volume control - since I can't really judge the volume level this way, I could cause quite some harm. Do you have any suggestions? Will something like a pillow or a bunch of (paperback-)books work well enough as an artificial head with regard to SPL-attenuation? Or is something like a semi-full cardboard box a better model for a human head? (And what everyday household-items do I fill the box with?)

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    1. There are bass lite and bass heavy versions of the DT770/600. They made a revision somewhere along the way and never said anything about it.

      That's why the Innerfidelity and Headroom graphs are so different.

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    2. @Dex, you bring up an interesting point about the soundstage. Anyone who's played with a parametric EQ and created a high Q (narrow) peak or dip in the response is familiar with the change in spatial perception--especially when it's in the midrange. So I suppose that could create sort of an artificial sense of greater "space".

      But I can also say the HD650 sounds even more open and spacious and has, what sounds like, more uniform response and far more accurate midrange than my DT770. So ragged midrange apparently isn't required for an open sound.

      I think human heads are pretty dense so stacked books are probably a reasonable proxy. The bigger trick is going to be the earcup seal--the books are flat but the sides of heads are not. I would also use pink noise and even then you'll probably find the measurement rather sensitive to both the position of the headphones and the microphone in the room. So it's essential to keep both as consistent as possible when swapping out the headphones.

      @Maverick, that's good to know. When it was discovered Sennheiser was swapping drivers between the HD600 and HD650 for a while that also produced some interesting inconsistencies. From what I understand the LCD-2 and T1 also had significant revisions along the way. At least I think Audeze bothered to announce their changes. Beyer and Sennheiser really should revise the model number with a "V2", "mk II" etc.

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    3. NwAvGuy,

      Thanks for these great reviews. What do you think are the best portable headphone amps for powering the DT 770-80? I'd like to spend around $100 or less on one, but I'm also curious to know what you recommend at a higher price point (I take it you'll say "the O2", for one). Sources will be an iPhone and iPod.

      Thanks again,
      Mark

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    4. If you can't afford an O2, I would say the FiiO E11.

      Delete
  79. Thanks. Does the E11 outperform the E7 (as a battery-powered amp) for this application?
    -Mark

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    1. Yes it does. It has more output, lower distortion, and less noise. The downside is the E11 can only run from battery (you can't use it while it's charging). See my E11 review.

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    2. Thanks! You're the best!
      -Mark

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  80. Hello once again, NwAvGuy!

    I've missed reading a new blog since digesting the ODAC 'official announcement.' Forgive me; I know the production of your blog is really and truly a gift to humankind from you and not the only facet of your life. Access to such clarity and honesty as represents your blog is addicting, though.

    I purchased barely used, mint condition Beyerdynamics DT770 Pro 80s a few days ago and have tried to listen to these 'phones with diligence.

    At this early stage in my experience using them, I have been moved.

    Let the audience be advised that my sources are compressed MP3 files stored in an Apple Touch 4G fed through a FiiO F3 LOD to a professionally assembled O2 (JDS Labs is the way to go in the USA). It is my opinion, having also used the O2 with Ety ER-4Ps and Grado SR-60s, that the 02 is tantamount to a perfectly straight wire of infinitely short length offering the sole characteristics of gain and near zero output impedance.

    Such characteristics are parameters I've only recently begun to appreciate in a manner akin to an awakening.

    At the risk of offending someone's sensibilities, I've nicknamed the 02 the "godbox."

    I've been struck by the ability, when listening using the Beyers, of my growing belief that I can more easily or effectively (truly) hear the distinctiveness (timbre, space and orientation) between whatever assortment of instruments and/or voices are sounding. It is as though the "boundaries" between each are more 'definitive' (as compared to the experience of using either the Grados or Etys).

    The Beyers have also (for me) come closer to the reality I've heard listening to live (unamplified) percussion, particularly wood - sticks - on metal - cymbals - and wood on wood.

    I don't know if these qualities are called "resolution" or "sonic accuracy/fidelity" or even if it is possible to express these experiences using words.

    The illusion of the stage is also noticeably wider than that produced by my son's Shure SRH-840s (also closed back, but not 'diffuse field?)'

    Oh, how I love this stuff!

    Live forever, NwAvGuy!

    Jonathan

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  81. @ Jonathan

    I've got the same feeling with my FiiO E17. All notes are just so much more distinctive and easier to distinguish. It feels more refined, effortless, elegant.

    Isn't it great.

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  82. @nwavguy - I couldn't have picked a better review to read, I love my HD650s for all the reasons that you mentioned in your HD650 review. Basically, I can listen to them forever. I have tried the Westone 4 IEMs and the AKG550s, but they were just tiring to listen to... putting the 650s back on made me feel like I was sitting in a perfectly fitting down easy chair.

    At any rate, I need some closed headphones for my new work environment, so others don't have to hear my music and you pretty much hit the nail on the head regarding comfort, the pads need to be velour... otherwise my ears get hot hot hot.

    The D770s seem to be great, but as soon as I started looking at them, I noticed that there are also the t70s. Has anyone had any experience with the T70 headphone and how it compares to the DT770?

    Also, can the Benchmark DAC (or a DAC with the same 0 ohm BUF 634) drive the 600ohm version of the headphones or should I just stick to the 250ohm cans?

    I'm just looking for some cans that can give me something close to the hours of pleasant listening that the HD650s give me.

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    1. The higher models of the DAC1, such as the Pre that I have, use internal gain jumpers for the headphone outputs. The jumpers allow high output, such as some 600 ohm headphones need, and lower output so you don't blow up less headphones and can get the volume control past the first 20%. I'm not sure about the "entry level" DAC1 or other BUF634 gear. The power supply voltages also determine the maximum output.

      I've never heard the T70 so I can't comment on it. You might not be all that happy with the mids and highs of the DT770. They do cause significantly more fatigue than the HD650 but I've heard much worse and they're physically very comfortable.

      Another headphone you might check out is the closed back Fischer Audio FA-003 which is also, from what I understand, now being supposedly sold under other names such as the Brainwavz HM5 and/or Lindy (Fischer's distribution was nearly non-existent). It's been described by headphone guys I respect as somewhere between the K701 and the HD600 in overall sound and physically very comfortable.

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    2. Thanks for the suggestions, I'll have to check out the FA-003/Clones to see if I can find one with velour ear pads as an option.

      Listening fatigue is definitely important to me... I guess I need to see if there are any stores in the area that have the D770/T70 and any of the other options.

      Maybe I just need to build a cone of silence and use the HD650s =D

      The other headphones that lots of people have suggested are the modded Fostex T50s (Thunderpants, Maddog, Paradox), that being said, it's hard to drop larger amounts of money ($300-700) on something where there's no real ability to return it if one doesn't like it. Though there's something very intriguing about orthodynamic closed headphones.

      Thanks for the thoughts on the DAC output, theres a DAC coming out that looks to be very much a clone of the Benchmark for $700 (complete with analog input, dual AD1855s and BUF634 headphone drivers)... don't know if it's something that you'd have any desire to test, if so, when I get it, I'd be happy to have them ship it to you to test and then just send you a UPS/FedEx label to send it along after testing.)

      Delete
  83. Hey Nwavguy,
    Thanks for the great review. Being new to this, I am still lost on whether a Fiio e7 and e9 combo will benefit me (got a deal on this combo). I do not listen at loud levels and will be powering the DT770-80ohm to my PC with my onboard sound:

    Realtek
    ALC898
    Output Resolution (higher is better): 24bit
    Max Sample Rate (higher is better): 192KHz
    SNR (higher is better): 110 DB
    Input: 24-Bit, 192KHz, 104dB

    Thanks for the help!

    ReplyDelete

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