DACs: Improve your USB (break out PCI USB card with Unison)

A few weeks ago I was saying that the USB ports on my ASRock x470/AM4 motherboard had less timing issues than the renesas USB card. This linustechtips video corroborates what I was saying in that they discover that AM4 boards actually have unusually robust USB controllers -- better than comparable Intel boards in this one regard, iirc. They seem genuinely surprised by the finding since AMD never hyped up the capability.



Maybe worth knowing if one's getting a computer just for music, but I still think it's a difference erased with better ddc's. If anything it's worth knowing that a more expensive Intel board wouldn't have hidden USB benefits as one might intuitively assume otherwise.

 

Who remembers the old pc days, assigning IRQ ports for our devices, sometimes to improve audio because the wrong channel would have interference from things like the mouse causing clicking sounds.

 

Is that what I was supposed to do decades ago to get mouse movement noise out of the audio chain?

I just changed pc.

 

Yep. I can't remember if the clicking was due to an IRQ conflict, or if it was some EMI from neighbouring traces on the pcb.

 

Apparently the original link points to a slightly different cards, not the one pictured. But still using Renedas so I recon should be the same outcome

 

What I have been kind of wondering lately is whether Unison better optimizes SQ as the host, or the slave. Seems likely having it at both ends would be ideal of course, but most of the comments till now have obviously been about Unison as the slave. Looking forward to comments on the Unison host with basically every other non-Schiit USB DAC.

 

Having trouble following you there. You mean with the Unison out via Urd and a non-Schiit DAC, I’m assuming?

 

Yeah that is it. A lot of people say Unison as the slave is an improvement over other USB implementations. I'm wondering if the Unison USB host is as big as improvement, absent having both (or more possibly I'm wondering if it is worth connecting my Urd to my Gungnir with Gen5 USB just for fun or would it make me sad. Would have to buy a cable.).

 

I confirm the card from post #1 is damn good. I immediately hear deeper and wider soundstage, and very tight and controlled piano reverberations. I wish I don't play this through $600 Dynaudio Emit 10 speakers.

 

@purr1n Is there a difference between PCIe ports fed from CPU PCIe lanes vs those fed from the chipset? It seems the x4 and x1 PCIe slots are from the chipset. Because they are all PCIe 2.0 and they share the bandwidth. When either of the x1 slots is occupied, the x4 slot drops to x2.

I also wonder if there is a difference between the CPU-fed vs chipset-fed mobo usb ports. your mobo has 4 usb 3.1 Gen 1 ports from the CPU, while the rest are from the chipset. It is known that high polling-rate usb devices interfere with each other. According to the linked article, not only does dedicating a USB bus help, but even dedicating a PCIe lane helps.

I am about to build a PC myself, but don't have access to an old PC to test this. Any help would be appreciated. I also think that figuring this out could lead to a useful and broadly applicable guide to good, cheap, set-and-forget USB audio.

 

I've recently found that a B450 motherboard can have issues with using 2 nvme drives, an x8 video card, a capture card, and USB audio at the same time. When one of those drives was SATA, everything was fine, but adding the second nvme drive introduced random audio cutouts in OBS recordings and in my monitoring, seemingly based on how busy the audio is. OBS doesn't record this happening in its metrics and the Auralic Vega on exact mode won't mute over it.

I know this is only tangential to what you're talking about, but maybe still useful info if you haven't finished that PC yet. Just get an X470 or better board on AMD if you use multiple pci-e ports and USB audio.