Topic: Fireface UC SPDIF loopback

Hi Everyone,

I am a new RME fireface UC owner and i have a question about using SPDIF. I saw somewhere that you could loopback the SPDIF connecion to record system audio back into the DAW without re-conversion.. great idea!

I tried this, and the results were interesting... I took a mixdown and played it out of Itunes and recorded into protools... sound was not so great! It sounded like a dulled down version of the song when i A/B with the original mixdown playing back beside the new recorded version in pro tools... i basically came to the conclusion that the itunes playback engine is pretty horrible.

so then i recorded directly out of pro tools and back into protools via SPDIF. The sound was much better this time but still the recorded file did not have the same stereo width and clairity of the original, but it was MUCH better than when recording out of ITUNES.

Since the SPDIF loop back didn't re-convert anything the signal sound be identical to the original, or no? How much quality loss is normal in this sort of situation? Is there a tweak or two i should do to the SPDIF settings to get better quality from the loopback?

My focusrite mixcontrol has a built in feature for loopback to the DAW which is suuuper handy. I find myself wishing for this feature in totalmix... SPDIF should be the next best thing??

Any suggestions are greatly appreciated smile



*****
macbook pro 13inch (2010 model)
4gigs Ram/ OS up to date
rme fireface UC
Protools 9
Logic 9
Cubase 5
1tb Gtechnology FW800 drive

Re: Fireface UC SPDIF loopback

HeadScratch The UC does have this feature, see section 31.5 in the manual, Recording a Subgroup (Loopback).

https://archiv.rme-audio.de/download/fface_uc_e.pdf

otherwise, there is no loss when using the physical SPDIF cable either, as long as you have playback and output faders at unity gain.

Regards,
Jeff Petersen
Synthax Inc.

Re: Fireface UC SPDIF loopback

hey thanks a bunch Jeff, I can't wait to get back to the lab and try this out!

Re: Fireface UC SPDIF loopback

Hello,

have you tried the Record option in DIGICheck (Function / Global record)? You can record anything what is played on the UC.

Regards, Onno

Re: Fireface UC SPDIF loopback

i'm probably a bit slow but the manual was a bit hard to follow on the activate loop back activation process lol....

"To activate this function, click on the white label in the third row while holding down the Ctrl-key. The label's colour changes to red."

What in the world is that ?? i still can't find the "label" they are talking about...

PLAN B: I youtube'd an overview of totalmix. They talked about loopback in it for a few seconds, and the guy just went to the hardware output he wanted to use, expanded a tool/setting pop-out and hit the loopback button... super easy!

i tried it, and it worked perfectly.. i removed the spdif cable and just used spdif hardware output for the software loopback instead. The recording sounded perfect, i like this much better!.... goodbye spdif cable and hello loopback button!

6

Re: Fireface UC SPDIF loopback

The new TotalMix FX comes with a full help by itself.

Regards
Matthias Carstens
RME