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


I posted this over at computeraudiophile, but got very little feedback, so I'm trying here. Looking for input from experienced users regarding sound quality of these two approaches. Right now I only have a SB Touch, but I'm considering a computer with external hard drive and a DAC:

Approach 1: Asynch USB. Wavelength Cosecant or Ayre QB9. About $3.5k. Just one input. Until I get a dedicated computer I would need to mod the Touch to output thru USB.

Approach 2: Super clock thru S/PDIF. PC to Offramp 4 w/Turboclock to Bryston BDA-1. About $3.5k too. More pieces in the chain, and more power cords and IC. Steve Nugent is a big supporter of this approach and says the DAC matters less IF you have a VERY good clock upstream. Initially I would use the Touch with the BDA1, then get the PC + Offramp.

All these DACs have discrete analog sections and all are very well thought of. My preferences are for soundstaging, 3D imaging, naturalness of the presentation and articulate, deep bass. FWIW, preamp is Lamm LL2 so I can only connect through RCAs. Amp is McIntosh MC275 (tubed).

Thank you!
lewinskih01
I initially went the USB route with Async dac and was satisfied - until I tried toslink with a decent cable - will never go back. Using an iMac so s/pdif is not an option unless I go usb to converter to s/pdif. Not convinced of the benefits over good toslink.

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

In the end I suppose it depends on the quality of the async design vs. the external unit.
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!
Async USB requires USB 2.0 compliant ports on the computer.

Most recent computers have this, although some netbooks and in particular Dell laptops can have high-latency I/O systems which can cause drop-outs with audio playback.

Steve N.
Empirical Audio
They are both valid approaches and either will sound very good. As always, it boils down to personal preference so nobody here can tell you which you will prefer.

Steve Nugent is a big supporter of this approach and says the DAC matters less IF you have a VERY good clock upstream.

Duh. that's what he sells so would you expect a different stance? Gordon Rankin at Wavelength is a big supporter of Async USB. The fact that these forums allow Steve and others to post about their products is free advertising for them so I don't blame them for doing it, but if you want an objective opinion you can disregard what Steve or any other manufacturer says about his own products.

USB is not limited to 16/44.1.

.
"Duh. that's what he sells so would you expect a different stance?"

If you read my posts, I recommend many other companies DACs, driven by my Off-Ramp 4 (to hit lower price points and deliver great quality). Dont you think I would make more money selling my own DAC?

How many other manufacturers of DACs recommend other companies DACs? How about zero.

Steve N.
Empirical Audio
.

Sorry, I don't get your point. I'm sure you would rather sell them your $4,000 DAC, but if someone can't afford your more expensive offerings you recommend they buy something from you that doesn't cost as much. Either way you are promoting your own products and getting free advertising.

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Thanks all for the input. It's giving me food for thought.

Sandstone: Unfortunately I cannot audition as I live in Argentina and these pieces aren't available here. So it's down to an educated guess! I realize these are all good DACs. Maybe the tubed Cosecant is too much of a good thing with my tubed pre and amp. Have you been able to compare your QB9 against other DACs? I would be interested in your findings. I won't be able to run it balanced, as my pre only has RCAs.

Herman: I realize Steve is likely to be skewed towards his products. It's only natural for any designer to do so. I've actually exchanged e-mails with Steve and value his input, and have also told him when I thought he was a little off. Have also exchanged with Gordon and also value his input. But then I seek for user's input as less biased point of view. But when someone providing that feedback goes "Duh", like if I were retarded...that I find a little off too.

Anyway, all feedback is appreciated. Anyone else?

Thanks!
.

It wasn't "duh, you are retarded" it was "duh, you are stating the obvious."

Sorry if you took offense.

.
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!
I just replaced my SB Touch with CI power supply going into an esoteric G25U clock/upsampler (touch upsampled to 176k and reclocked) into berkeley dac direct into amps. I was thrilled with the sound until I put an ESI Juli@ sound card into my PC. I have a 10 meter aopgee BNC cable sending the Juli@ into the G25/berkeley (next room) and it totally blew away the touch. (Using JRiver 16). I loved my touch and thought it sounded great. I'm still blown away.
Cerrot: Thanks for the input. Very good to know this. I wonder how your system would perform with an asynch USB to S/PDIF converter with a super clock vs. the Juli@ + G25 feeding the Alpha.
BTW, you mentioned your PC is next room. How do you control it from your seat?

Sandstone: Thanks for the clarifications. As you said in your first reply, it looks like I cannot go wrong. Yet there is certainly one option that would provide the best bang for the buck, but without auditioning it's all but imposible to say which one it is. Maybe the real question behind this is whether I can live without a CD player.
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.
Lewinskih, I wouldn't be trying a usb interface anytime soon. The interface is inherently flawed. Always has been, always will be. I think PC audo is best in its purest form, through a sound card via an spdif 75 ohm output. Converting the usb to audio is just too messy to sound "right". As for controlling J River, I did install Rivermote to use off my iPad. It's okay, but looking for better. I am looking into something more versatile, which may be via DLNA.
Converting the usb to audio is just too messy to sound "right".

Strange, I've heard a number of USB DACS that sound marvelous. Your blanket statement is as untrue as all horn speakers honk, all tube amps sound bloated, all transistor amps sound sterile, all vinyl playback is compressed and noisy, all systems with a passive preamp are lifeless, and any number of other unfounded stereotypes.

Properly implement USB is the basis for a great system.

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I want to OUTPUT from spdif to INPUT to USB Ayre QB 9 (USB only).
Any suggestions w/o fooling with the software?
Thanks
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.
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,