Asynch USB or super clock thru S/PDIF for $3.5k?

Good luck, and please let us know if you find one.

Steve,
"Async USB requires USB 2.0 compliant ports on the computer"

Shouldn't the rest of this sentence read as follows? "....if resolutions in excess of 24/96 are to be supported"

For instance my Ayre has a dip switch option (Rsrv A) for USB Class 1 where it still runs in Asynchronous mode, but is limited to 24/96. 24/196 requires Rsrv B setting for USB 2.

There's also this:
http://thewelltemperedcomputer.com/HW/USB_DAC_AsyncSlow.htm

Best,

Lewinskih01,
Your post suggests that for your first approach you may have already verified that Ayre QB-9 and other asynch's can now play well with the Touch. I know there was at least a percieved problem earlier, but it may be OBE. That said, please consider home-auditioning both of the GREAT options you are considering.

I own the Ayre QB-9 and can tell you that it is one amazing piece of gear that not only manages all the standard issues of external digital clocking (Wavelength's solution), galvanic and RFI isolation,etc, but also has this incredible analog stage with zero feedback topology, all in one single box. Plan on running in balanced output if possible. Around $2100 used on Agon.

As you know, many on this site will swear by Steve Nugent's approach, esp. for integrating high quality computer audio with existing components. His systems are incredibly well reviewed and awarded in national forums. IMO he's also one of the more experienced, knowledgable and generous contributors to Agon threads. It seems I recall that there may be a 30-day trial option for his gear? I think Steve's systems may also be favored if the computer must be located a longer distance from the DAC (a USB cabling limitation).

Good luck. My guess is you are win-win on this.

Meiwan,
"Not a big usb fan as I believe format passes 16/44 only, so even with a converter you are downsampling, then up sampling...."

I think USB 1.1 supports 24/96 native, and with proper drivers, USB 2.0 supports 24/192 as well as other even higher rez formats.

"In the end I suppose it depends on the quality of the async design vs. the external unit."

Right on!

Lewinskih01, After owning or listening to a long list of earlier generation DACs and CD systems, I currently own the Bel Canto 3.0 and Ayre QB-9 (192Hz version). I prefer the versatility of the Bel Canto and use it sans preamp, w/balanced ic into a Jeff Rowland amp for my second system.

But I can summarize my impressions of the Ayre by saying that short of something like the Playback Designs DACs at $5-7K or perhaps the ARC-8, it is the most analog-sounding and yet revealing digital device I've ever owned or heard, even better than the Ayre CX-7E in my system.

If RFI/EMI is reasonably low, using RCA outs doesn't seem to be a significant issue for my playback of the Ayre, though others may wish to comment. Mine isn't a fair A-B, since my (Cerious)XLR cables are much better. I did observe minor but noticeable effects across USB cables during high-resolution(24/192) playback. Belkin Gold or Cardas Clear both seem to work fine for me.

Hope this helps, and good luck!

Lewinskih01,
"Maybe the real question behind this is whether I can live without a CD player."
I noticed an interesting factoid on an audio trade news blog yesterday, to the effect that upwards of 80% of CDs now sold in the USA are thought to be played only once - ripped to other media and then reproduced from electronic storage.
The figure sounds high, but whether accurate or not, we seem to have reached a level in audio quality and convenience that renders CD players much less important.
In any event, my CD player is not improved by routing it through my DAC, and I almost never use mine anymore (esp. since discovering the Theater View mode in JRiver Media 15!).
Other issues aside, the simple fact is that it's now easier to extract bit-perfect (e.g.,amplitude perfect) data away from the EMI/RFI nightmare known as a PC box, with advanced clocking to eliminate virtually ALL jitter in the time domain.

If you need multiple I/O options, suggest you also consider the Antelope Zodiac Plus as a design that includes world-class clock, DAC and analog stages. It seems to make sense that eliminating extra cabling and boxes, and positioning of the clock as close as possible to the DAC stages are all worthy features.

Marcober, I'm quite certain that you can't do it yet.
I'm assuming that you're still trying to connect Ayre with your Squeezebox, because that's likely the only reason on the planet for trying this.

If you've been keeping up with John Swenson, et.al. over at the Squeezebox Touch forum, then you already know this has been a quest of several years for them. More recently, it seems the impedance matching issues with S/PDIF interfaces (which according to the forum are often non-standard) have risen their head yet again.
Regarding connecting the QB-9, even with planned SBT software mods to support USB out in general, it's my understanding that Asynchronous mode isn't supported.