Importance of source quality with asynch USB DAC?


I have never tried computer audio and I'm considering either a great DAC with mediocre synchr. USB in, such as Bel Canto DAC3, or an asynchr. USB DAC such as Ayre or Wavelength. The advantage of the former being I can use my CD player as source until I can buy a new computer, and the advantage of the latter being I can simplify the system.

So my question is how important is the quality of the source computer with an Ayre QB-9 or Wavelength. My current laptop is a Dell Latitude 420 (I believe), which is 4 years old. Alternatively I could use an even older Sony Vaio PC, but that's old. I know people rave about Mac Mini + an asynch USB DAC...that would be my goal down the road, but how would it sound in the meantime, compared to a Bel Canto DAC3 fed thru S/PDIF from a Rotel CD player as transport?

Thank you!
lewinskih01
There's people who'll argue how important asynch is, and those who don't think it makes a difference. I saw the guy from Beresford arguing it doesn't make a difference on a forum.

As with everything else in audio, I'd be willing to bet the technology in and of itself doesn't make every asynch DAC superior to every non-asynch DAC. Kind of like tubes vs SS, class D vs A/B, etc. I'd say audition what you can and take it from there.

I'm pretty sure the Ayre DAC only has a USB input and nothing else.
From what I've read the source really doesn't matter for "regular" or asynch USB DAC. The "smarts" are in the DAC to handle some sort of flow control for a "regular" DAC and it's up to the DAC to provide the timing. If you're using a laptop for just sending PCM out USB you don't need a lot of computing power. I use a Netbook connected to a QB-9. No need for a fancy USB cable, too.
Larry,

You have a nice system! And a dedicated room!! Congrats.
How does the netbook + QB-9 sound compared to your Esoteric DV50?
Where do you store your music?
Anything to look for in the laptop/netbook/pc that could/would impact sound quality if using the QB-9?
Are you using iTunes? Anything else?

Sorry for all the questions.

Horacio