When I say you can hear the differences, it boils down to Round Trip Latency aka RTL.

I've told you what to look for:

Quote:
If a new interface is not advertising the following: "Fast USB 2" or faster and 192/24 and "near zero latency", I would buy one that does.


The earliest of these new devices shipped October 2019. It's easy to tell what devices are using these and I was able to figure out the OEM from the descriptions. The 8 I/O (4 mic-pre+2 DI+2 Line In–Out+2 headphone amp) version of this chip costs $6.73 each, min. qua. of 1000. That's why everyone is using it. Well… almost everyone: Audent and iConnect are not. Someone's buying the old stock that doesn't meet the good specs so, what are they saving per unit? $2–3?

Faster means USB 3 and Thunderbolt 3. The real world differences between these and Fast USB 2 work out to the same as moving your ears 12" (USB 3) or 18" (TB3) closer to or further from your monitor speakers. Use the speed of sound at sea level when you do the math.

There's no such thing as zero latency but the "near-zero" claimed is so fast that you'll hear comb filtering due to phase anomalies when monitoring the I/O through your computer at a 50/50 mix. It goes away at 60/40 or 40/60 so you no longer need dedicated monitoring apps to compensate (MOTU calls theirs CueMix—not applicable to their M2/M4, BTW).

M-Audio, MOTU M2/4/Ultralite 5, Scarlett 3rd Gen, Mackie FxProv3, NI, PreSonus, SSL and many others are using this.

If it has the right terms, buy for the feature set. I have a MOTU M4, three Mackie FxProv3 mixers with different channel configurations and an M-Audio air 192|14 that I use daily. Although the guts are the same as everyone else, M-Audio adds an additional pre-amp circuit that lets me use my ribbons and SM7B—most others can't.
M-Audio 192|14 at Sweetwater

All the ones I have use an I/O mix/blend control that I find extremely convenient—otherwise, I'm setting that up in my DAW. None of the Scarletts have this—the only reason I don't recommend them—I'm spoiled. If you look at the M-Audio above, it's the knob at the upper left corner.

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