Does Schiit's Unison USB obviate the need for a streamer to improve quality

I know streamers have their purpose to make it easy to play music across a wired or wireless network, but they are often recommend as a way to put ethernet between the source and output which improves quality.

Now that Schiit is shipping all their upgradable DAC’s with Unison USB, I’m wondering if it’s still recommended to use a streamer to improve music quality? Unison USB offers the following advantages:

* A completely unique USB input receiver based on a Microchip PIC32 microprocessor with Schiit's proprietary code.
* Complete electromagnetic and electrostatic isolation.
* Self-power by the DAC for the critical low-noise re-clocking and latching sections.
* Precision local clocks for both 44.1 and 48k multiples.

Their previous USB Gen 5 already had “Complete electromagnetic and electrostatic isolation” which is essentially the same as putting Ethernet in between. They even used the same transformers that are used in Ethernet devices. Did you miss Gen 5?


I have a Modi 3 and it’s not clear to me if it has gen 5 USB or not? I would assume not since the Modi 3 is powered by USB. But they were clear that they only added Unison USB to their ugradable DACs which the Modi 3 is not.

Unison is definitely better than Gen 5 for Yggdrasil. I was a Unison tester and preferred it with a lowish-cost Allo USBridge + LPS to a couple of more pricey AES streamers, which in turn were better than the same USBridge (or a microRendu) into Gen 5. But I’ve never used it directly from a PC or Mac, so I don’t know how well it performs in that situation vs the USBridge configuration I used for a while. At this point, I prefer streaming AES from a Pi 2 Designs Pi2AES+Pi 4B running Ropieee than the USBridge into Unison, but it’s a subtle difference. All in all, Unison is a good improvement and it brings Yggdrasil USB to approximate parity with AES – for this DAC.

1 Like

Firstly I wouldn’t read too much into the marketing. For instance the use of different clocks for different multiples is normal practice in any quality DAC and doesn’t really have anything to do with USB inputs specifically. I think it is safe to say Schitt began behind the curve with USB and have put a lot of work in to narrow the gap and maybe even take a modest lead with this innovation. But interestingly the use of microprocessors can also allow certain processes like MQA via the USB input so I’d like to see how much grunt that pic32 processor has and see wether it is comparable with the XMOS devices now doing a similar job in other DACs.

If you don’t know Schiit, from their FAQ:
Hell no.

The ONLY WAY you will get this answered is to get the Unison and try it out. Everything else will just be speculation, as what others hear and comment about may, or may not, be equal to what you hear and experience.

I did the upgrade on my Yggy, and I do enjoy the sound. I go direct from the fanless NUC to my Yggy with USB, and did the same when the Yggy had the Gen 5 USB board installed.

Since I only have the one Yggy, and it took time to do the Unison USB panel install, I have to go by memory, not a direct A/B comparison. But the change was equal or better, and certainly not worse.

I played four specific songs that I know from various artists very well to have them in memory the best I could. The selection of songs I played an hour before the upgrade did sound excellent when I played them again after the upgrade.

If I had to grade it, Gen 5 USB was 4.5/5 compared to Unison USB being 5/5. I understand that may seem arbitrary, but again, how I hear things may, or may not, be similar to how you would hear the same things. So, me using “clarity”, “soundstage”, “depth”, “warmth”, etc. are just as arbitrary, in my mind.

Do I recommend the Unison USB as an upgrade, Yes. Is it great to have it in the new Schiit components that use it, Yes. Did it rock my world and change everything, No. Am I happy with it, Definitely.


When interviewed face to face, the response was “hell no, but we are keeping an eye on the situation”! I think their decision was a brave and principled one but they’ve taken their knocks since and commercial necessity could still force them down that path. However the smart operators have offered it on certain inputs and kept others free of it. Offering it as a bolt on option would be the very definition of smart.

Thank you very much for your insights. I agree the only way for me to decide is to try it out myself. Regardless, your account of your experience with your Yggy was interesting and informative. Best regards!

Roughly how many hours to runin the unison usb card
For it to smooth out ?

My experience is with Yggdrasil, which is notoriously slow in getting up to top performance after being turned on. I’d say 1-2 days, but that’s rather subjective.

Does this mean that you are having sound quality issues? Or is this more just a general inquiry to see if others have notices a sonic difference after a bit of time?

After I did the upgrade in my Yggy, I played music for about 11 hours straight. Played some well know favorites with great dynamic range to see if I could hear a sonic difference. Then went on to some very clean and “black silent” classical and acoustic music selections. Followed by some nice Jazz with complex rhythms.

I did heard a bit of a upgrade to typical sonic buzzwords (clarity, sound stage, resolving, etc) from the Gen5. The more I listened, the less I was thinking about the sonic differences, and the more I was thinking about how outstanding the music was.

So, then I just decided to rock out hard for the next 6 hours!!

So for me, the run in was less than 10 minutes and no sonic differences since then. I would probably venture to state that there is a great chance, the burn in time was actually Zero (0) minutes, and that first 10 minutes was actually just gratitude that the upgrade was just that, an upgrade, and not just a lateral financial spend.

I don’t think you’ll get many (if any) acoustic/electrical engineers that will provide scientific reasons why there would be any “burn-in” time for a USB connection that would equate to sonic stabilization over time.

I recently upgraded from the Schiit Modi 3 to the Modius that came with Unison, after a brief detour with a Gold Note DS-10 that I was able to review. The Gold Note was light years better than the Modi, but the difference between it and the Modius were surprisingly small, although the Gold Note does a lot more.

I have found that the Modius makes a real difference to the bass and mid bass over the Modi 3, the sound feels more solid.

Has anyone used USB out on a NUC running ROCK direct into the unison USB? I seem to remember some issues in the forum about ROCK on NUC having issues going directly to the previous Gen5 USB input on Schiit audio DACs

Yes, I have this without any issues from my NUC to my Yggy. Although, I didn’t have any issues with the Gen5 before I did the upgrade to Unison.

I also have this setup. No issues.

I upgraded my YggY to Unison. Similar experiences to others here. I have used my SurfacePro3 and an RPi4 to drive the YggY. Both sound fantastic, but I think the RPi has a slight edge in smoothness and detail retrieval. Could I tell them apart in a blind test? Dunno. Anyway I use the SurfacePro as a Remote now and love the convenience.

Both have benefited from a USB power isolator - a simple device that disconnects the endpoint USB power and inserts a clean 5Vdc from a separate power supply. iFi and others make these isolators and they are about $50 US.

I also built another Pi with an AES hat and have gone into the YggY AES input. Again, this combo sounds excellent - can’t really tell it apart from the Unison USB. Every time I think I hear a difference I switch back and can’t.