[Andrew_WOT]

My take:
-With Stello DA100 I was unable to find any audible differences in favor of SPDIF, in fact USB seems to sound a tad smoother.
-With Headroom MicroDAC the situation is different and feeding it from Transit versus directly from USB provides slightly better SQ, not night and day but quite noticeable to not turn back to USB anymore.

 

[Pendergast]

I hope you all enjoy your setup!

I am using mostly DIY stuff...

I am using a powerbook as a source, with all the music froma separate drive, connected thru Firewire. The output goes through USB2 in a HagUSB (converting USB to S/PDIF), which is coupled to a DIY DAC.

I also have a portable cd player (sony), with its digital optical output connected to an upsampler (Monarchy Audio) which is connected with an RCA cable to the DAC.

I have also added to the DAC a manual switch, so I can go from the computer or from the PCDP as a source.

I am using a DIY amp (from Bottlehead) with DIY speakers and I can barely perceive a difference between the sources. When the volume is cranked to the max, the setup is totally silent.

Maybe it is me, or maybe this set up cannot provide a difference. Either way, I am fine with it.

 

[uzziah]

your mac has bit perfect optical output?

if not, and you care about it (which perhaps you should) i'm getting one of these:
http://www.diykits.com.hk/dac.html
and several folks have them; apparently bit-perfect with asio4all and pretty cheap; ofcourse if it's just for transportable use then PERSONALLY i'd just want something very small with dac/amp that just plugs into usb (doesn't meier make something like that?), one piece



ps: as far as the great "digital transmission" debate, generally here are highlights:

1.coaxial usually better than optical
2. except if you have electrical issues with say.....a PC optical means no ground loop
3. usb can be good, but the current implimentation of it leaves a lot to be desired


and in the end: it doesn't matter all that much, try to get bitperfect if you can, and then just try what's most convienient and if you have problems try something else; not something really to stress over unless your going very high end

 

[325xi]

USB audio is always (correct me if I'm wrong) isochronous, which means inevitable high jitter.

SPDIF coax is naturaly jittery, and also can pick up EMI/RF noise from nearby HF electronics.

Toslink has its own issues

 

[audioengr]

Quote:

Originally Posted by 325xi /img/forum/go_quote.gif USB audio is always (correct me if I'm wrong) isochronous, which means inevitable high jitter.

The Creative Audigy 2 NX uses asynchronous USB protocol, and there are others used in the pro arena.

 

[325xi]

Quote:

Originally Posted by audioengr /img/forum/go_quote.gif The Creative Audigy 2 NX uses asynchronous USB protocol, and there are others used in the pro arena.

I wouldn't take a chance by using anything of Audigy family in my system.

What are others? I remember last year's reply of one of audio designers on Asylum that asynchronous USB chipset for audio isn't available yet - this is why all standalone USB DACs are isochronous.

 

[audioengr]

Quote:

Originally Posted by 325xi /img/forum/go_quote.gif I wouldn't take a chance by using anything of Audigy family in my system. What are others? I remember last year's reply of one of audio designers on Asylum that asynchronous USB chipset for audio isn't available yet - this is why all standalone USB DACs are isochronous.

IT requires a custom design - no OFS chips support asynch. See USB-audio.com for others.