Entry-level USB Audio Interface comparison

Discussion in 'Headphone Amplifiers and Combo (DAC/Amp) Units' started by Serious, Apr 9, 2020.

  1. Serious

    Serious Inquisitive Frequency Response Plot

    Pyrate BWC MZR
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    First up, pardon if this is the wrong subforum to post it. At first I was going to post it as a reply to my post in the all purpose advice thread since I don't think too many people will care about this comparison, but maybe some will find it interesting. I was initially going to post this much earlier, but I still think it's relevant today, so I'm still going to post it.
    An old TerraTec DMX6Fire USB interface that my dad didn't need anymore started giving up the ghost recently, so I looked for a replacement. I used to use it for some rough vinyl rips and as a mic preamp with phantom power for gaming.
    In the price range that I was looking at I only found the Steinberg UR22C, Focusrite Scarlett 2i2 Gen 3 and finally the MOTU M4. Another option would be to buy a used Clarett range Focusrite, which also seems like a viable option. I compared the sound as an ADC unless otherwise noted. Made vinyl rips and compared them across three different systems.

    Steinberg UR22C
    • AD/DA: Forgot, will update asap
    • Sounded the warmest, still - tonality is just slightly warm
    • Most lacking in plankton
    • The stage also seemed the smallest
    • Transients somewhat rounded, everything just sounds smoothed over
    • Slight grain aswell
    • Overall I thought this one was clearly the worst
    • Still, the input mix volume button and being able to use the 5V power switch as an on/off switch when not connected to an external 5V PSU were features that I felt the 2i2G3 needed.
    Focusrite Scarlett 2i2 Gen 3
    • AD/DA: CS4272 (seemingly)
    • Lean tonality, lacking in bass weight and treble is a bit too bright
    • Less grainy than the UR22C though, overall a more liquid presentation
    • The tonality is overall too lean for me to be enjoyable without EQ - I'd have to EQ the recordings.
    • Despite this, no measured difference in FR. Spectrum looked virtually identical for the vinyl rips aswell.
    • Stage is a bit wider and just slightly deeper. Overall a bit more competent in the technicalities: Definitely more resolving and better clarity.
    • Still lacks macrodynamics
    • Overall it seemed slightly better in the technicalities than the TerraTec that it replaced, but the tonality is worse
      The TerraTec sounds similar, but slightly warmer. Also seemed mostly grain-free.
    MOTU M4

    After I was dissatisfied with the two other USB interfaces I also bought a Motu M4. I bought the M4 for its input monitor mix knob, which I thought was a fantastic feature the UR22C has. I liked being able to hear exactly what the other person hears through my microphone and being able to adjust my volume so it sounds natural. Like many people I don't usually like hearing my own voice, but I really like this feature.
    • I couldn't find which ADC it used, so I opened mine. AKM AK5554VN ADC! Perfect!
    • Dedicated power button. I don't get why so many other interfaces lack such a basic feature. Inevitably they will stay on and die much earlier due to component failure. My TerraTec probably wouldn't be dead now if it had a proper power button.
    • This one has a very different presentation to the other two that is hard to explain.
    • Right off the bat it sounds warmer than the 2i2 Gen 3, but also not as warm as the UR22C. Closer to the UR22C, though and if anything leaning slightly warm.
    • I'm still unsure about it, but I think it's a bit grainy. Nothing dealbreaking and overall it sounds more like the 2i2G3 sounds overly smooth at times despite its bright tonality.
    • Overall it just seems to sound more colorful in the way it presents different sounds. That's the part that is hard to explain for me, but it just seems to leave more of the instrument's sounds intact. Seems to have a broader palette of timbres and sounds if that makes any sense.
    • I think it plays a role in the above, but it also just sounded a bit more vivid in general. Microdynamics seemed less compressed.
    • I think it also resolves a bit more low level information than the 2i2G3, though not as much as you'd expect given the otherwise very favorable impressions. A lot of it is still missing.
    • Bass extension is also slightly lacking. UR22C seems to go the deepest subjectively. 2i2 is similar.
    • The inputs seem to clip 1dB quieter than the specs indicate according to my measurements. I redid the measurements and this is not the case. Either way, a normal XLR DAC output will clip the inputs at the minimum gain. Will need to use attentuators. I wish it wasn't that way.
    So this is the one I ended up keeping. Despite being slightly more expensive than I initially would've liked to spend, it was the only one I thought was a decent upgrade over my TerraTec thingy.
    One thing that put me off was that it uses a SABRE DAC, so I'd have to listen to SABRE during gaming. I found that this was one of the warmer SABRE implementations, though. It seems like they really tried to smooth over the sandpaper treble of the typical SABRE DACs. I even found the sound out of the headphone output to be slightly better than the other two interfaces: Slightly larger stage, more resolving of low level information, better clarity.
    It's not as good as a GO2A (even from its SE output), but I found it usable and definitely more than good enough for gaming.

    The 2i2 and UR22C sounded very similar when used as an ADC and as a DAC, not so the M4, though. M4 sounds decidedly smoother and more natural as an ADC compared to its DAC section. I'd recommend it more as a ADC than using it as a real audio interface for driving powered monitors, for example. But even in that case it does the job.

    Also the small LCD panel is immensely useful for getting the correct volume. It's helped me on multiple occasions to set the gain for my mic. Helps to see just how compressed modern music is, too. It even has 64dB of gain as compared to the 56dB of the 2i2G3. Doesn't help much with my fairly sensitive condenser mic, but using an inefficient dynamic mic it's probably a very good thing. I also seemed to get slightly less noise from the mic output when testing the limits of my mics (when digitally compensating for the gain difference). But getting the noise level indoors low enough to properly test it is virtually impossible.
     
    Last edited: Jun 17, 2020
  2. bixby

    bixby Friend

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    Thanks for the impressions.

    I had thought about simplifying a bedside rig with something like the Motu 2. My previous experience with Steinberg UR12 and Audient ID 14 left me wanting more, when I tried going that route at another time. I suppose the Motu is the best of the under $200 bunch though. I still feel the need for at least entry level separate dac and amp for my listening only use case.
     
  3. luckybaer

    luckybaer Friend

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    How did you config the Motu for vinyl rips?
     
  4. Serious

    Serious Inquisitive Frequency Response Plot

    Pyrate BWC MZR
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    I recorded all of them as 24 bit/192 kHz. Buffer size probably 256 samples which I think is the default. From the phono stage into the soundcard using an RCA to 1/4" TS plug cable. Could also use an adapter and regular RCA cables. Gain on the M4 set to minimum. Recorded with Audacity, no extra resampling, etc. Basically probably the simplest way to do it. Some seem to prefer bypassing the phono stage and a digital RIAA compensation, but I haven't tried that yet.

    Yeah, personally I feel it won't replace an entry level rig. As I already mentioned I prefer the GO2A soundwise. Then again I've recently been listening to it with my HD800 more than I'd like to admit. In fact I was just listening to it before switching to the GO2A. It's quite warm and surprisingly inoffensive sounding. Or rather somewhat midrangey. Bass is quite limp sounding aswell. It's probably interrelated, but I think the whole presentation is a bit soft (transients smoothed, microdynamics reduced aswell) and also a bit closed in. Yet from memory it managed to sound a bit warmer (but kinda rougher treble - GO2A alleviates the SABRE-ness better), while also having a larger stage than the 2i2G3.
    Different price-range and product category, but I wonder how it compares to the RME ADI 2 Pro soundwise.
    Note that I'm only referring to the HP outs so far. I bought some TRS to XLR adapters so I can use the balanced outputs. Might be interesting to see how it fares bypassing the HP out which I feel is the weakest link.
     
  5. Serious

    Serious Inquisitive Frequency Response Plot

    Pyrate BWC MZR
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    After @purr1n posted about how much he liked the Motu UltraLite mk4 as a DAC and general purpose interface, I decided I had to try the M4 as a DAC aswell. (Well, I knew I had to try it, but this put it higher up on my to-do list) So I left on the M4 and GO2A for more than 24 hours to get them to sound as good as possible. I spent some time comparing the two vs my Gungnir Multibit A1 this afternoon. I only listened to music streamed from TIDAL, mostly shitty, compressed modern recordings.

    The gist is that the headphone out is very gimped compared to using it as a DAC. The headphone outs aren't really worthy of consideration other than for convenience. While I preferred the GO2A (even SE) as a unit, when using it just as a DAC the roles reverse.

    LH Labs GO2A Inf, green filter, gain maxed, most recent firmware (Balanced TRRS, GND left floating)
    • 0dBFS sine = 6.556Vrms = 16.33dBV = 18.55dBU
    • Warm up is necessary with the GO2A, otherwise it's way too harsh. Fortunately you get most of the benefit very quickly. It sounds almost as good after 15 minutes as it does after 24 hours.
    • Man, that's some fat midbass. It lacks articulation, but compared to the GO450 I kind of like it. Sounds bigger than it looks.
    • It takes some warmup to get the best treble smoothnes. And warm it gets. I measure surface temperatures about 25 degrees over ambient, in my case 48°C.
    • Treble smoothness after warmup is very good considering it's a SABRE, but it's still not quite perfect.
    • Macrodynamics are by far the most limited of the bunch, more so than the micro stuff.
    • Imaging in the bass (don't laugh) is by far the least precise here. Seems to be a symptom of its fat, but unrefined bass.
    • The top octave is noticeably rolled off subjectively. By far the most rolled off in this comparison.
    • It has the most hiss by far, but I'm not sure I can hear it at reasonable listening levels. The M4 and Gungnir MB seem similarly noisy (both less noisy than the GO2A).
    MOTU M4, Balanced TRS out
    • 0dBFS sine = 4.957Vrms = 13.90dBV = 16.12dBU
    • Warm up seems to mostly affect its clarity and like with the GO2A it also helps alleviate some harshness.
    • I think it's overall the most neutral sounding of the bunch. Definitely the leanest in the bass. Low bass and upper treble seem somewhat rolled off, the rest seems flat.
    • Treble sadly seems to have somewhat more of the SABRE sheen than the GO2A Inf. It's far from the worst and the gap is slight, but overall the GO2A edges out the M4 in treble smoothness.
    • Imaging is more precise than GO2A, soundstage slightly wider with a tiny bit less depth. However the precision feels rather fake. Images seem oversharpened and generally do not seem to change in size much between the instruments.
    • Microdynamics are a notch above the GO2A, but still a far cry from the Gungnir MB.
    • Clarity is very good, seems to be the best here. Makes the other DACs sound veiled in comparison.
    • Possibly as a result of this clarity the transient "snap" (for lack of a better word) seems to be better than the Gungnir MB, but the macrodynamics overall still seem to be behind the Gungnir MB.
    • Treble extension seems to be in between the Gungnir MB (most extended) and the GO2A (least extended).
    Schiit Gungnir MB Analog 1, USB Gen 5, Balanced XLR
    • 0dBFS sine = 4.144Vrms = 12.35dBV = 14.57dBU
    • The Gungnir MB is still by far the most involving DAC with the best microdynamics and resolution of these three. The M4 really does not seem to be better than the GO2A in this regard, although the GO2A seems to have more of a tendency to compress volume levels subjectively.
    • Timbres and textures are more convincing.
    • Soundstage is roughly the same size as the M4, but it varies more between recordings.
    • Similarly the imaging can go from pinpoint to diffuse for different sounds within the mix, more so than the other DACs manage.
    • I'm sure it's interrelated, but the imaging seems to be better than the two other DACs aswell.
    • Often times I found myself listening to the whole song instead of the 1-2 minute snippet I listened to for comparing the DACs.
    • Despite its sweet treble tone, the top octave is actually the most extended here.
    • Bass is also somewhat fat and rounded.
    Overall I'm not really sure what we can reasonably expect from the M4 and I also don't know how other modern DS DACs sound, so take this FWIW. I still think the Gungnir MB Gen 1 is a much better DAC, but that's not a fair comparison. The GO2A Infinity is a more fair comparison, but considering its compact size it punches above its weight for sure, especially when used balanced. Still, considering the price of the M4 and its features I think it's about what we can expect. Based on what Marv wrote about the UltraLite mk4 I'd expect it to sound a bit better than the M4.

    I may revisit this comparison in the future as I feel I don't quite have a perfect grasp on how they compare yet, but I feel confident enough in my impressions for posting them as is. Would also be interesting to check out the M4's SE outputs.
     
    Last edited: Jun 16, 2020
  6. Serious

    Serious Inquisitive Frequency Response Plot

    Pyrate BWC MZR
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    I should've realized this before, but the back panel inputs 3/4 have a higher maximum input level. Ordered adapters to try them out.

    According to my measurements**:
    Input 1/2: XLR 0dBFS = 10.38 dBU
    Input 1/2: SE 0dBFS = 16.68 dBU
    Input 3/4: XLR 0dBFS = 18.81 dBU (SE in T/S config should be the same)
    Overall very close to the specs, which are 10dBU and 18dBU for the balanced inputs respectively.

    I recorded some DA/AD loops to compare the two input pairs and it seems that the inputs 3/4 do sound somewhat more spacious and a bit more resolving. Somewhat less flat, more involving. The difference isn't as large as I expected, but it's there. Comparing my Schiit Gungnir Multibit/MOTU M4 chain vs the other files posted in the Gearslutz AD/DA diffmaker thread it's really no slouch. I'm talking about actually listening to the files, instead of looking at the numbers.

    Inputs 3/4 also have slightly lower THD and higher bandwidth, it seems*. However I had to use line level attenuators with the inputs 1/2 for the DA/AD recordings, so it might not be quite fair to compare them that way.
    It seems like @philipmorgan wrote more or less the same thing in his excellent post in the M4 thread: Mic input is surprisingly capable, but inputs 3/4 are more transparent. Although he mentioned that input 1/2 get padded down and then reamplified, while it seems if anything it's the other way around. The inputs 3/4 need a higher input voltage to clip. Likely it's just a different amp section.

    *I can post loopback measurements if someone's curious, but someone already posted loopback measurements on ASR. I think it's a lot of work simply to confirm that the specs are accurate. The A/D filters seem to have very low passband ripple, with the D/A section perhaps having somewhat more of it. Seems to be linear phase throughout.

    For completeness: MOTU M4 does seem to use digital volume control throughout. Generally 1dB per step on the inputs and outputs and 0.5dB on the mixer. As mentioned here.

    **Note these are PEAK values, not full-scale sine level values, which sadly doesn't go without saying. Like others on this forum I don't approve of the notion that a full-scale sine should be 0dBFS. Full-scale sine level values will be 3dB quieter than this.
     
    Last edited: Jul 3, 2020
  7. Cspirou

    Cspirou They call me Sparky

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