S/PDIF Loopback

[taven_mk]

Hello. I have focusrite 6i6 and i want to record my pc's output sound in my DAW. But it doesn't let me loopback in software so i use a S/PDIF loopback cable between in/out. Does it create any signal loss or degradation in tone any? Focusrite team said it doesn't because the signal is digital but i read a lot of bad things about S/PDIF. How can i test?

[steve]

i want to record my pc's output sound in my DAW

What's your DAW?
Where does Audacity come into this?

If you want to record sounds that are playing on your computer, with Audacity, see: http://manual.audacityteam.org/man/tuto ... puter.html

[taven_mk]

Thanks for the answer. I use NI Maschine as DAW and couldn't figure out how to use windows WASAPI driver in it . So i use the loopback cable...

[steve]

For support with NI Maschine, please use this site:
https://support.native-instruments.com/ ... 5-MASCHINE

[taven_mk]

Thanks but my main question is:

Does it create any signal loss or degradation in tone any? Focusrite team said it doesn't because the signal is digital but i read a lot of bad things about S/PDIF. How can i test?

I know the Native Instrument's web address...

[steve]

S/PDIF is digital, but that does not necessarily guarantee that it will be bit-perfect.
Unless it's broken / not working correctly, then the quality will be very good even if not bit-perfect.

It will not be bit-perfect if there are any buffer underflows or overflows, and will not be bit-perfect if the digital audio is resampled.

To test if two tracks are identical:

1) Line the two tracks up so that the waveforms match when zoomed in (http://manual.audacityteam.org/man/zooming.html) to sample level (so that you can see the individual dots).
2) Apply the "Invert" effect to one of the tracks (http://manual.audacityteam.org/man/invert.html)
3) "Mix and Render" the two tracks together (http://manual.audacityteam.org/man/tracks_menu_mix.html)
4) There may be sound at the start and end if the two tracks were offset, but if the audio data is the same (bit-perfect) in the two original tracks, then the overlapping region will now be silent.
5) To check if the middle section is absolutely silent, select that region and open the "Amplify" effect. If the selected region is absolutely silent, the Amplify effect will say that the "New Peak Amplitude (dB)" is "-Infinity".

[taven_mk]

Alright... Thx again.