S/PDIF over Analog - Big Difference?

[Phuturistic]

I have a Proteus 2000 unit that I'm sending a stereo signal into a MOTU 828mkII via 2 balanced TRS monster cables. Both units have a s/pdif rca jack as well. If I use the s/pdif, will it make a big difference in sound quality? I'd be dropping an A/D conversion, so I'm assuming it would help. I know I would need to clock to the Proteus digitally as well.

Thnx

 

[Blue Bear Sound]

Yes - big difference... avoiding unnecessary A/D/A conversions greatly improves overall quality, particularly if the converters involved are NOT great to begin with.

 

[dwillis45]

I'd be dropping an A/D conversion, so I'm assuming it would help.

I don't think you would be "dropping" an A/D conversion. If you route the signal SPDIF OUT from the Proteus to SPDIF IN on the MOTU, the signal will remain digital as it's passed via firewire to your computer. I think the question is which unit (Proteus or MOTU) has the best A/D converters. The best way to answer that is to record both ways and compare. I would guess that the MOTU would do a better job since that's one of it's primary tasks. But who knows! As you suggest, the other issue is clocking. You would have to change your software settings to reflect the fact that the MOTU was being clocked by an external digital source. I assume the Proteus has some sort of clock although I couldn't even guess about the quality.

 

[tkingen]

In the past I was routing my DAW stereo outputs via a Delta1010 card to the Delta1010 breakout box via spdf, then analog to a Presonus Central Station. As an experiment I tried going directly from the card to the Central Station via spdf and heard a great difference in fidelity.
It's still hooked up both ways and it's interesting to compare once in awhile. The comparisons always make me switch back to the card > Central Station in a hurry.