Why this makes the server a little less important may not be terribly obvious, but here it is - a good computer design, with quality power supplies that regulate the CPU and other hardware - including the on-board oscillators - means that it will probably sound better than one without that good, quality power delivery. Async USB does just that, and a proper implementation does do wonders for the elimination of jitter, something DAC chips are notoriously sensitive to. Well, after you’ve done a quick tour, let me welcome you back by claiming categorically and without any serious justification that just about everyone has agreed that the spooling data into a DAC using the high-quality oscillators (clocks) in the DAC itself, instead of those in your crap-ass computer, is a better solution than relying on the clocks inside a computer. Well, it’s not that the server doesn’t matter - it does - it’s just that some things have happened in the computer audio space that tend to make it all a little less important. So, before I go any further, let’s take a second and talk about why the computer might matter.
Look - the whys and wherefores may be mysterious but as I’ve argued elsewhere, my lack of understanding doesn’t entail any particular ontological status. Some folks, perhaps those that consider themselves more “objectivist” among the propeller-head crowd, may consider the very notion that a server would make an audible contribution at all as some sort of heresy. Namely, that it was the best thing since sliced bread. Way back in the day, I remember a lot of fuss and bother about the audio superiority of the PowerMac G5 floated by the Computer Audiophile crew. Oh, right - since I retired my PowerMac G5, which means about 18 months or so.
I’ve been using my trusty (dusty) MacBook Pro as a media server since I dunno when. Spitting Bits Power Mac G5 - Super Audio Server Extraordinaire!