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October 12, 2011

Turtle Beach Micro II

tb micro ii benchINTRO: This is the first in a series of inexpensive portable USB DAC reviews I’ll be publishing in the next week or two. The idea is to test the DACs with a high impedance load (such as the O2 Headphone Amp) and a typical headphone load. The DACs are all small, easily portable, and USB powered. The $25 Turtle Beach Audio Advantage Micro II is just such a DAC. According to Turtle Beach, it’s supposed to provide “higher quality sound” compared to internal PC audio. I also have updated how I test and present DAC results.

TURTLE BEACH MICRO II: The Micro II is a small “dongle” with an attached 2 inch “pigtail” USB cable. It has a single 3.5mm jack which serves as line out, headphone out, and an optical digital out (using a supplied 3.5mm-to-Toslink adapter). There’s no volume control, other controls, or inputs of any kind--just a blue LED.

tb micro ii modesWINDOWS INSTALLATION: The Micro II installed smoothly in both XP and Windows 7 without needing any drivers. Windows reported it as a “USB Sound Device”.  The only sample rates and bit depths available are 16/44 and 16/48 as shown to the right in Windows 7.

SUBJECTIVE SOUND QUALITY: There was moderate hiss with my Ultimate Ears IEMs but the Micro II was fairly quiet with less sensitive headphones. The sound quality, however, was seriously odd. Playing familiar well recorded audiophile tracks the Micro II made them sound shrill, glaring, and harsh regardless of what headphones I used. I was really curious to measure the Micro II and find out why it sounded so obviously bad.

POOR DRIVER DESIGN (updated): I first checked the Micro II’s frequency response and it was reasonably flat out to 15 Khz so the poor sound was still a mystery. Then I checked the 1 Khz THD and while it wasn’t great it also wasn’t bad enough to explain the poor sound quality. When I dropped the level to see if the distortion would drop, I found the problem. The Micro II was displaying a horrible linearity problem. Dropping the input from 0 dBFS to –20 dBFS should drop the output by 20 dB as well. But it only drops 8 dB! That’s a massive 12 dB error. The net effect is the Micro II was heavily compressing music—making softer sounds much louder than they should be.

BAD SOUND EXPLAINED: It turns out, as described in the comments to this article, the C-Media CM102 integrated USB sound chip apparently used in the Micro II has a “feature” called Dynamic Range Control (DRC) that defaults to on. Confusingly, there’s an advanced option in the Windows 7 sound options for the Micro II simply labeled “Loudness”. And, worse, it’s enabled by default. You have to uncheck the box to stop the Micro II from heavily compressing anything you play through it.

DRC vs LOUDNESS: The Turtle Beach choice of calling the C-Media’s DRC option “Loudness” is very misleading. In audio, Loudness Compensation involves changing the frequency response at low listening levels to compensate for human hearing. It’s generally based on the Fletcher-Munson Equal Loudness Curves. In this case, however, it has nothing to do with changing the frequency response—only the overall dynamic range. I don’t know what Turtle Beach’s driver calls this feature as it’s an unsigned driver so I didn’t install it on my test bench PC that runs the dScope software. The whole idea is to not need proprietary drivers.

WHAT WERE THEY THINKING (updated)? The “loudness wars” are already out of control without any further help from Turtle Beach. A lot of pop music has a peak to average volume difference of only around 8 – 12 dB as the labels keep compressing music ever further in an effort to have it stand out as being louder. The last thing pop music needs is another approximately 12 da lot more compression but that’s exactly what you get, by default, with the Micro II. For anyone unaware of the option, or who knowingly leaves it on, the Micro II is likely to sound significantly worse than the internal audio of just about any computer its plugged into.

MEASUREMENT SUMMARY: The overall results, even with DRC disabled, are not terribly impressive. The high frequency distortion, in particular, is poor. Here are the results compared to the more expensive FiiO E7 (some tests were run slightly differently but I’ve tried to adjust for that in the E7 numbers):

Measurement TB Micro II Fiio E7
Frequency Response 20hz-15Khz 33 ohms +/- 1.8 dB Fair +/- 0.1 dB Excellent
THD 0 dBFS USB 10K 0.20% Fair 0.05% Good
THD 1 Khz 10K Ohms -3 dBFS 0.022% Good 0.03% Good
THD 1 Khz 33 Ohms -3 dBFS 0.12% Fair 0.03% Good
IMD CCIF USB 0.28% Poor 0.03% Good
IMD SMPTE  0.03% Fair 0.008% Excellent
Noise A-Weighted -93.8 dBu Fair -96.7 dBu Good
Max Output 33 Ohms Vrms/mW 1.26v 52mW Good 57 mW Good
Max Output 10K Ohms Vrms 1.34v Good 1.4v Good
Output Impedance 100hz 0.95 Ohms 0.13 Ohms Excellent
Jitter USB 16/44 Jtest Fair Very Good

BOTTOM LINE: In my opinion the “Loudness” feature enabled by default is an epic fail. Someone either got sloppy or they have very odd priorities for a “high quality” USB DAC. Putting that aside, the rest of the performance of the Micro II still isn’t very impressive. The next several reviews of low priced USB DACs will help put the Micro II’s performance in perspective.

 


TECH SECTION


FREQUENCY RESPONSE: The frequency response with a 10K load (such as a headphone amp) at 16/44 is acceptable but not great. There’s a fraction of a dB of variation below about 30 hz and it’s down –1 dB at about 15 Khz. The steep roll off above 12 Khz is typical of a cheap DAC running at 44 Khz and is due to cost savings in the digital and analog filters. The slight peak around 8 Khz is also disturbing as it indicates either poor DAC filtering and/or potential instability in the headphone amp. Into 33 ohms you can see a slight drop due to the output impedance and a low frequency roll off of about –1.7 dB at 20 hz. That’s borderline audible. Into 16 ohms it would be even worse and more likely to be audible. This indicates less than ideal capacitor coupling in the output:

TB Micro II Frequency Response 100K (blue) & 33 Ohms - 3 dBFS ~400 mV 16-44

 

THD+N vs OUTPUT: This test starts at 10 mV and the rise at below 250 mV is more likely due to more quantization error than noise. The unweighted noise should be below 0.004% but the distortion is more than ten times higher. The lower blue plot is into 10K and the distortion is around 0.025% which is under the worst case guideline of 0.05%. Into 33 ohms, however, it’s over 0.1%  above about 700 mV which could be audible under some circumstances. In both cases, the maximum output level is around 1.3 Vrms. This works out to 52 mW into 32 ohms, 104 mW into 16 ohms and only 6 mW into 300 ohms:

TB Micro II 1 Khz THD N vs Output 10K (blue) & 33 Ohms 16-44

 

THD+N 100 hz 0 dBFS & OUTPUT IMPEDANCE: I now run this test at 100 hz as that’s where output impedance is usually most critical due to the resonance frequency of many headphones. A low 100 hz output impedance keeps the frequency response accurate and provides electrical damping of the driver which can improve the quality of the bass performance. The test is run at 0 dBFS input to reveal any digital overload problems such as the NuForce uDAC-2 exhibits. The Micro II does not reach clipping even at full volume into 15 ohms. The distortion here is mostly in the DAC itself and remains similar into 100K even at lower volume settings. The resulting output voltages at 100K and 15 ohms are used to calculate the output impedance. The Micro II’s distortion is relatively poor at 0 dBFS. It hit 0.14% into 100K and 0.21% into 15 ohms. The output impedance was 0.95 ohms which is acceptably low and it’s slightly lower at 1 khz due to less impact by the output capacitors:

TB Micro II Max Output & Impedance 100 hz THD N 100K & 15 Ohms (blue) BW=22 Khz

 

THD+N vs FREQUENCY: Here’s the 1 Khz THD+Noise plotted from 20 hz to 20 Khz into 10K (yellow) and 33 ohms (blue) at 775 mV (0 dBu). The input is –3 dBFS to prevent any digital overload of the DAC. The increase in low frequency distortion into 33 Ohms is another sign of a capacitor coupled output. The rise from 0.05% to 0.15% is likely the output capacitor’s non-linearity. The drop above about 6 Khz is related to the bandwidth limit of 22 Khz as the harmonics move past the audible band. The sharp rise again above 10 Khz is due to very poor high frequency performance in the DAC (and/or filter) despite the fact the harmonics are cut off:

TB Micro II THD N vs Freq -3 dBFS 0 dBu 10K & 33 Ohms (blue) 16-44

 

SMPTE IMD: The result here is marginal but acceptable at this price. Ideally all distortion products should be below –80 dB but that’s not the case. The spread (or “mountain”) at the base of the 7 Khz signal is another bad sign. This test is run below the DAC’s digital limit and also well below the maximum output (at 0 dBu) into 33 ohms. It’s somewhat better into 10K but not a lot:

TB Micro II SMPTE IMD -3 dBFS ~0 dBu 33 Ohms 16-44

 

CCIF IMD BENCHMARK DAC1 PRE: This is a more challenging test, and again, the goal is to have everything except the 19  and 20 Khz signals below –80 dB. To show how it can look, here’s the result with the Benchmark DAC1 Pre:

Benchmark DAC1 IMD CCIF 33 Ohms ~400mV

CCIF IMD MICRO II 44 Khz 33 Ohms: By comparison, here’s the same test as above from the Micro II. There’s an entire “forest” of distortion products above –80 dB with the 1 khz difference signal at –52 dB which is very likely audible. The digital/analog filters in the Micro II are in real trouble here as might be the DAC itself. The two spikes around 15 Khz exceed –40 dB and may also be audible. This is admittedly a tough test for a cheap DAC running at 16/44 but this is still a much worse than average result made worse by the headphone amp struggling with a 33 ohm load:

TB Micro II CCIF IMD -7 dBFS ~0 dBu 33 Ohms 16-44

 

CCIF IMD MICRO II 44 Khz 10K: Removing the load results in the 1 Khz difference signal improving significantly from –52 dB to about –72 dB dropping the reading by a factor of ten. But note there are still a lot of spikes above –80 dB and even above –60 dB within the audio band. Worst of all, the spikes at 15 Khz are still crossing –40 dB:

TB Micro II CCIF IMD -7 dBFS ~0 dBu 10K 16-44

 

CCIF IMD MICRO II 48 Khz 10K: DACs will typically do better on this test running at 48 Khz but it depends on their filtering and design. In this case, things get significantly better but are still not great with the 10/11 Khz signals still around –40 dB and several other spikes still above –80 dB. If your operating system lets you run a DAC at 48 Khz, 99% of digital music will be re-sampled from 44 Khz up to 48 Khz by the operating system with mixed results. In this case, it’s hard to say which would yield the better result. In XP it’s not an option as the DAC is forced into 44 or 48 Khz depending on the source sampling rate:TB Micro II CCIF IMD -7 dBFS ~0 dBu 10K Ohms 16-48

 

NOISE & LINEARITY: I’ve changed this test slightly to use units of dBu rather than my previous dBr referenced to 400mV. 0 dBu is 775 mV. The Micro II’s –93.8 dBu A-Weighted noise referenced to 400 mV would be 88 dBr (it’s always a difference of 5.7 dB). That’s decent noise performance for a USB powered DAC but falls well short short of what’s required for reasonable silence with the most sensitive IEMs. The goal is –103 dBu. I’m also now showing the absolute (unweighted) noise in microvolts. The linearity was fairly good with an error of only 0.8 dB at –90 dBFS:

TB Micro II 1 Khz -90 dBFS Noise & Linearity Ref 0 dBu 10K

 

-20 dBFS LINEARITY WITH “DRC”: With the “Loudness” option enabled (which is on by default) here’s what happens with a –20 dBFS 1 Khz signal. It’s played back at –8 dB instead of –20 dB. The Micro II is raising the level by a whopping 12 dB as part of its “Dynamic Range Control” feature. This is why, by default, it sounds relatively awful:

TB Micro II 1 Khz -20 dBFS Vol=100% THD N BW=22Khz ref 1.34 Vrms

 

JITTER: Here’s the spectrum from the dScope’s J-Test for jitter. The side bands are average at –110 dB but the “spread” of the signal is relatively poor indicating significant low frequency jitter. The frequency accuracy (clock accuracy) is very good as shown by the frequency reading on the left:

TB Micro II Jitter 11025 hz J-Test 10K ref -3 dBu 16-44

 

RMAA RESULTS: Out of curiosity I tested the Micro II with RMAA with the DRC/Loudness option enabled (10K load). While the frequency response was very similar, the THD spectrum showed some significant differences although the 2nd and 3rd harmonics were similar. The IMD was even worse than the dScope measured and could have been a clipping/level problem. The noise measured a relatively poor –77.5 dB for which I have no explanation. It presumably limited the dynamic range to a similar value. Interestingly, there’s no solid indication of the DRC compression. RMAA missed the huge linearity problem. The results are shown below along with the sound hardware by itself (2nd column) in loopback. For more, see my RMAA article:

TB Micro II RMAA Summary (10K Load)

TB Micro II RMAA Freq Response (no load)

TB Micro II RMAA THD N (no load)

TECH COMMENTS: The good news is the output impedance is below 2 ohms, the noise/linearity is decent, and the frequency response and midrange distortion are semi-acceptable into a 10K load like a headphone amp. Into 32 ohm headphones, however, the distortion rises to unacceptable levels and the high frequency distortion into any load is even worse.

32 comments:

  1. Thank you for the review, if only I now know what to avoid. It's a pity that you've wasted your time on this product.

    According to the optional driver and the web, this sound card is powered by the C-Media CM102-A+/S+ chip: http://www.cmedia.com.tw/ProductsDetail.aspx?C1Serno=2&C2Serno=2&C3Serno=5&PSerno=17
    What you describe as horrible linearity may actually be a feature C-Media calls "Dynamic Range Control".

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  2. nice and quick. I'm waiting till you sir will find something better then e7 if its possible in this price point.

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  3. When reviewing DAC's, can you produce measurement plots similar to those Stereophile produces (but with standardized axes, so we can compare / overlay like with like )?

    E.g. linearity error (16-bit data), dBr vs dBFS, etc

    Would this have shown up / illustrated the issue you discovered with the Turtle Beach better than your existing plots?

    Going forward, would it have made continuing testing worthwhile, as then you could show just how flawed this device was, compared to other, better measuring dacs, and highlighted the fact that you can't rely on just one metric, but you need to see the whole picture?

    Keep up the good work.

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  4. @Inarc. Thanks. Short of warning people away from the Micro II it was indeed a waste of time. If the CM102 has some sort of dynamic range processing it should not be enabled by default with no way to turn it off via native Windows drivers.

    @Anon, my reviews are still works in progress and I'm trying to bring more of the tests in line with Stereophile and InnerFidelity. The whole dBr vs dBFS vs dBu issue complicates things but is easy enough to correct for. The problem with dBr is it requires specifying the reference used for every single test--something even Stereophile doesn't always do. But dBFS and dBu are self-referenced and always mean the same thing for any test, on any test equipment, with any gear.

    Some of John Atkinson's tests will remain different for some good reasons. For one, he's using an Audio Precision which presents some of the results differently. And headphone gear, portable players, and USB DACs are a minority of his tests so he optimizes things a bit differently.

    As for finishing the TB Micro II testing, it's just not worth all the time. I'd rather spend my limited free time on more worthy hardware.

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  5. Good job on the review, though I would suggest that all subsequent tests are done at the maximum native samplerate of whatever DAC you're testing. Many chipsets perform internal samplerate conversion when the audio stream in not in their "native" maximum samplerate, and that can be very problematic. Case in point, most AC-97 implementations, Creative 10k1 and 10k2 chipsets etc.

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  6. The Micro II only runs at 44 and 48 Khz and, unless someone is more into movies than music, they're most likely to feed it at 44 Khz. I did verify the huge linearity problem is the same at 48 Khz. I agree some DACs do better at their max native sampling rate, but 99+% of music is 44 Khz. So it makes the most sense to test at 44 Khz.

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  7. Wow. It really looks like they really are taking the loudness war to the hardware level which is pretty sad.

    I like the idea of a, "Warning, it sucks!" article for when you happen to come across something seriously flawed like this.

    I agree that you shouldn't waste your time with extensive measurements of something so seriously flawed but on the other hand a quick post with the preliminary results is very useful because the vast majority of this stuff has little to no objective information available anywhere.

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  8. You should try the Syba SD-CM-UAUD with Cmedia CM119 dongle thing since it's so cheap and easy to find. Doesn't sound that great, but did make the T50RP sound very BIG and appears to have MASSIVE amounts of voltage. I can only use it on 2 or 3 out of 100 on the Windows volume. Might was well find out what a $7 dongle can sound like compared to the more expensive ones, right? Someone should also send you an Emu 0204 so you can try and find something that has similar performance for a cheaper price, considering you'd said it should be possible to make something without the microphone preamps for even cheaper. I suspect it also performs much better than people are reporting at higher impedance from its headphone jack (that doubles as a line out) for things like the Beyerdynamics of 250 and 600ohms and the Sennheiser HD580, 600, and 650. It still makes the ER4S at 100ohms sound better than the E7 and that's a damping factor less than 5.

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  9. If I had to chose between the SoX resampler in FB2K's DSP and the hardware resampler, I'd chose the former. In any case, this is getting offtopic. How about re-evaluating the UCA202 as a line-out device and posting your thoughts about it? Supposedly (though you didn't get into details about it) the line-out is transparent.

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  10. I've got a hunch that the cheap FiiO DACs will crush this little monster. Can't wait to see some more tests, especially since I didn't know about this particular unit so my product knowledge is increasing. I'm really hoping for a sub $100 unit that emerges which can hold its own against an HRT or CEntrance device.

    One product that may be fun to play with is the THX TruStudio Pro stuff from Creative, like the X-Fi Go! or the Surround 5.1 Pro. I've heard they're not as universal from a driver standpoint, though. I just wonder if THX is any good in the consumer world.

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  11. After the hard work in the O2, reviews come again! Thank you for your wonderful blog.

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  12. NwAvGuy, there is another interesting question about DACs, which is the internal sample rate versus external.

    I've heard that some DACs run internally at 48000Hz, so if you feed them at 44100, they will use a non-optimal upsampling mechanism. So you can get better quality doing the upsampling in software (that's easy in Linux with pulseaudio) and using the DAC at 48000Hz. Is that true?

    By the way, is the E7 internally upsampling everything at 196Khz? If that is true, what mode is better, 44 or 48Khz?

    Thanks.

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  13. Nice quickie. One must wonder how many other consumer PC devices share like flaws, either from poor q/a, flawed design, or most nefarious, purposely done to fool the buyer.

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  14. Poked around - datasheet for device specifies "DRC" (Dynamic Range Control) is defaulted to ON. Can be disabled via advanced properties of device in Windows control panel. Not specified if this requires exposing of function via their (unsigned - ugh) "driver".

    A bit sneaky, IMHO, will likely have typical consumer / naive reviewer thinking it sounds "better" due to higher average levels.


    Rob

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  15. Somehow I had the feeling that not all USB DACs could be created equal...

    Are you maintaining some summary page with links to all reviewed DACs and a short summary table of their results? I'm thinking of how my Behringer UCA202 compares to the others and keeping track of all the results.

    Thanks for the test.

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  16. I have one of those and noticed the same problems you did. But using the optical out there seems to be no (audible) problem. Could you test the optical out?

    Oh, and congratulations for your site, it's very hard to find places that treat audio as a science and not as voodoo.

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  17. @Reticuli, I already have the Syba CM119 and it too has some significant problems but not the dynamic range issue. Stay tuned for that review. :)

    @akgk171 I have the FiiO D5 and it also uses a similar C-Media integrated chip. It's has some significant problems like the Syba.

    @heycarnut, Thanks for the posts. I just checked again, in XP there are no options with the native XP drivers. In Win7 under the "Custom" tab there's a single word "Loudness" and it is indeed checked by default. I run the dScope usually in XP so I would need to take a different approach to measure the Micro II with that option turned off. I'll consider doing that but that still leaves XP users a victim of either the TB drivers or lots of forced compression.

    This is a classic example of really poor design and/or marketing. While I can see a portable player offering an option for compression to help in noisy environments like commuting on a bus, train, flying, etc. It's much harder to envision why someone trying to upgrade their PC's internal audio wants their music heavily compressed by default. And, as I reported in my subjective comments above, it sounds BAD.

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  18. Hhopefully, this is the beginning of a great series of reviews! (I'm really curious about the performance of other popular products.)

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  19. In light of what was said in previous comments, I'd definitely advise updating this article. Calling a compressor a "linearity error" is likely to elicit a frown from anyone remotely familiar with DACs or sound processing, and I don't think you want to sound like you're talking out of your rear end.

    Anyway, it appears there is quite a demand for inexpensive USB soundcards, especially ones that do well driving headphones. Something in between a CMedia-based USB sound stick and a FiiO E7 (which is nice but around 100 bucks already). Any opinions of Creative's current offerings?

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  20. To me, dynamic range control defaulting to ON would make slightly more sense if this thing had a mic input. Range compression is fine and dandy for VOIP or other voice communications with a headset. Still it seems like a dumb move. Thanks for the heads up about this one. Next!

    By the way, while people are throwing idea out, did you have any plans to test any computer onboard audio? e.g. Realtek ALC882 or ALC889 or whatever is common. I get the feeling that the performance of these would be sensitive to whatever else is on the mainboard and the layout there, as well as whatever else is running inside the box, but that might make for an interesting baseline comparison.

    Some of the chips advertise SNR of 108 dB or so on playback, and they can do 24/96 and more. Even if 108 dB is referenced to full scale output and is a bit optimistic, that's still pretty good. But that's just paper specs.

    I mean, I'm pretty sure the THD and IMD isn't amazing anyway, but some quantification would be nifty.

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  21. I find it quite ironic that C-Media provides surprisingly thorough measurements in the datasheets of its mediocrely (and worse) performing integrated chips.

    By the way, what's up with the subpar loopback RMAA test results? Just another RMAA inaccuracy?

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  22. Since the Behringer UCA202 has already been mentioned, the ADS Technologies RDX-150-EF using the same PCM2902 chip may offer slightly better performance: http://www.birotechnology.com/soundcards/html/
    I personally am more interested in 24-bit USB audio class interfaces, though.

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  23. @Stephan, I agree with you, although from a measurement perspective, it is a linearity problem and results in compression just as I described. It's even less accurate for Turtle Beach to call it "Loudness" which implies frequency compensation at low volume levels rather than overall compression.

    @Mikeaj, the chip S/N (and/or dynamic range) specs are often highly unrealistic. 96 dB is the best you can get over 16 bit USB undithered, add in some USB power supply noise, etc., and things only get worse from there.

    @Inarc, the loopback distortion is somewhat high (but hardly awful) because the poor pro-audio interface was being used with TRS to RCA adapters which ground one side of the balanced outputs. The output distortion wasn't an issue testing the Micro II as I was only using the inputs. It performs much better looped back with balanced cables. I normally use my Benchmark DAC1 and ADC1 for RMAA testing but they're "in service" elsewhere at the moment. It also could be partly a level issue with RMAA's flawed calibration routine.

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  24. I have a CM103+ device (USB speakers DAC) and at least under Win XP it is possible to disable the DRC "feature". It sounds decent without compression, but RMAA measurements are pretty awful still. Also there is a problem with levels. If maxed out both in master and wave controls, there is a massive distortion, easily heard over headphones. I wouldn't even bother measuring those crappy all-in-one chip C-Media designs.

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  25. First of all, enlightening review and thank you very much for your great site, keep up the good work. I deeply appreciate your articles about audio basics which helped me very much in understanding the 101 of audio engineering (although I still have to look a lot of things up in recent articles and wikipedia).

    Your upcoming series of reviews of USB DACs is interesting because I am currently looking for such a device. My problem is that the spiral cable of my Audio Technica M50 (closed headphones, impedance 38 Ohm) is too short to use it comfortably when sitting on my desk. Therefore a USB DAC I could just plug into my USB hub would help me very much. The quality from my internal PCI soundcard is okay (low but noticeable hiss) but anything better is welcome.

    The problem is, I would just go with an external amp like the FiiO E5 although these headphones don't really need an amp due to their low impedance and high sensitivity. But I assume I would violate the 1/8th of impedance rule with most of the available headphone amps.

    Therefore I am still looking for a suitable solution, hopefully something will unfold in your upcoming reviews.

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  26. Any word from turtle beach? Could you test this on a linux distro for control group?

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  27. With the DRC mystery solved, I've run additional tests on the Micro II and substantially updated the article above. Thanks again to those who caught the obscure setting.

    @Anon, the E5 won't violate the 1/8 rule but it doesn't make the best desktop amp as the battery will go dead if you turn off your PC (although if you have a powered USB hub that will charge with the PC off that might work). Check back for the other USB DAC reviews. One might work for your needs.

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  28. Slightly OT, but I just went through some RMAA results on the web, and thus I'll boldly state:

    Some of the best bang / buck in terms of PC audio is...
    *drum roll*
    ...a well-implemented Realtek ALC889 or ALC892 on your motherboard.

    (OK, it's not exactly news. But still, these chips show excellent measured performance. Just like onboard audio in general, Realtek has come a looong way.)

    They should slap on a hi-def USB interface and sell it as a one-chip USB sound solution - so much better than the usual CMedia stuff it's not even funny. Even a PCIe interface might be interesting, though I'm not sure of demand these days.

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  29. Article suggestion: WASAPI shared vs. exclusive mode (or ASIO), is there any difference in sound quality?

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  30. @vittau, I plan to do some more research for a future article on USB audio including jitter, re-sampling, "asynchronous mode" USB, bit-accurate reproduction, 16 vs 24 bits, blind listening tests, etc.

    I think there are a lot of myths, and misunderstandings, surrounding USB audio. The main reason to use ASIO and exclusive mode, AFAIK, is for recording not playback. As long as it's a bit-accurate USB stream, and there are no dropouts, I don't think you can change the playback sound quality (or measured performance) of a given DAC using different driver modes.

    The Computer Audio link in the right hand column of this blog is interesting reading if you haven't seen it. Benchmark also has a good white paper on USB DACs and jitter--there's a link in my jitter article.

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  31. @ mikeaj
    >>"To me, dynamic range control defaulting to ON would make slightly more sense if this thing had a mic input."

    Turtle Beach has a companion product in the Amigo which does actually have mic. It's probably their more popular product since their gear is aimed primarily at gamers on the cheap. So whether due to error of omission or laziness, the loudness toggle is probably on because of that.

    ~Armaegis

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  32. I have 24 ohm HD 201 headphones. How would the bass roll off/distort? Would it still be bad?

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