Pc to DAC Configuration


Hello all,
Presently, my DAC is located next to my IMac Pc.From there I'm running 30'
inter connect cable to the preamp which is residing on the main audio rack.
My question is: Would it be sonically beneficial to move the DAC back to main rig , so I can use my high end audio cable and thus eliminate r f distortion
that's associated with such long runs?
My proposed configuration would be: IMac>12' USB>Bel Canto 24/96 USB Link>12'S/PDIF>DAC.
Will this configuration be better than my current set up?
Thanks all of you for your response.
Regards,
Rod
rodvujovicsr
It depends a lot on the analog section of the DAC ect. You may also consider using just a 24' long spdif cable.
In my first attempt at computer audio, my setup was similar to what you are proposing, except that my USB cable length was 6 feet and my S/PDIF cable length was over 20 feet. This was not a great solution. The long S/PDIF cable resulted in lots of jitter, which was plainly audible.

Your proposed solution of a 12 foot USB + 12 foot S/PDIF would probably be a little better, but I suspect it will also result in audible amounts of jitter, unless your dac does a very good job with jitter reduction.

Bryon
I have my music server(computer) next to my rack with the dac(usb) and the rest of my electronics. I use a remote computer to operate the server wirelessly. It is fantastic! I am using windows 7 and jrivers. They are great together. I could not be happier with it. I am a vinyl guy, but, finally digital makes sence. I am still a vinyl guy with digital on the side.
The USB interface on the BelCanto is Adaptive, not Async, so it is sensitive to jitter. I had a similar interface (CEntrance) in my older products. Need to use a good quality 1-1.5m cable.

If you used a newer async USB converter, then you could go with a cheap 16-foot USB cable and shorten your analog interconnect. This would be an improvement in jitter and minimize analog degradation and it would support 176.4 as well as 192.

Steve N.
Empirical Audio
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Transparent is now saying that their new USB cable can be used over lengths exceeding what is normally the maximum for USB devices. (This is possible because in audio the send-ack protocol for block mode transfers doesn't happen.) It's also not crazy expensive like some Transparent cables.

The was a recent Positive Feedback Online report on a number of USB to SPDIF adapters, several of which were async. (I'll also note that Steve N., who posted above sells one. I don't currently own any of Steve's products, but his products have an excellent reputation. Also note that Wavelength has a async USB to SPDIF converter now, too.)

If I was in your shoes, I think I would try running USB the entire distance from your computer to your other gear. The USB would go into an async converter that was right at the DAC. (The Audiophilleo converter is especially interesting because it is small and light enough to be connected directly to your DAC's SPDIF in, with no cable. But in any case, you could use a very short SPDIF cable.) Then use good quality 1-meter interconnects from the DAC to your preamp or amp.
How would you describe the sound of this plainly audible jitter?

In my system, the reduction of jitter resulted in three audible improvements: Increased perceived resolution, improved imaging focus, and the removal of high frequency harshness. So, to answer your question, the sound of jitter in my system was decreased perceived resolution, diminished imaging focus, and the presence of high frequency harshness.

If you are wondering how I know that these improvements were attributable to the reduction of jitter...they resulted from the addition of an Empirical Audio reclocker - its raison d'etre is the reduction of jitter.

Bryon
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Tvad - I'm using the dac in the Meridian G68, so that I can make use of the G68's bass management and EQ.

However, since robust software for bass management and EQ are now available for Mac, I've been thinking of buying a new dac along with a Mac mini, and keeping the G68 for movies only. I recently borrowed a Wyred DAC 2 from a friend, and I was impressed.

Bryon
It is possible to build your own USB cable and get 10m length to work. I have not tried it myself, but customers have. See:

http://www.instructables.com/id/How-to-Extend-yout-USB-using-UTP/step2/The-making-of-Part-1/

Steve N.
Empirical Audio
Thanks for the responses.

After reading your posts on this matter , I decided to go with long USB cable. There are a couple of new cables on the market that might do the job- Wire World Starlight USB (7M) and Transparent performance USB.
If any of you have experience with these cables,please let me know.
Thanks again for your time.
Rod
I have the Starlight. I think it is a good cable, and has been very well reviewed by a number of users. I can't say that it made a big difference in my system -- but I have an async DAC, and the cable may not be as important as it is with other DACS. Also, my cable is fairly short, so you may notice a bigger difference among cables.

I'm sure the Transparent is very good, too. I might have gone that route, but frankly it was a lot easier to buy the Wireworld cable than to deal with a Transparent dealer, so I went with the Starlight.
Just a little update: My Mac Mini died (being repaired now), so I'm running a 15 ft. el-cheapo USB cable from Staples out to my laptop. It sounds very, very good. I'm using the Wyred 4 Sound DAC-2, which has async USB, so that's probably a factor, but at this point I'd definitely try the long USB cable if I were in your situation. If it doesn't sound great, consider getting one of the async converters discussed above.