Roland Quad Capture - mystery inputs

[JapanAxe]

In the process of teaching myself to use Reaper, I have come across an anomaly with my Roland UA55 Quad Capture interface. I have been using it without incident for the last couple of years. It has 4 channels of audio in (2 on mic/line inputs, 2 on SPDIF), and 4 out (2 line, 2 on SPDIF).

In the documentation, input channels 1 and 2 are mic/line, while 3 and 4 are the combined stereo channels of SPDIF.

I have noticed that the audio devices page on my iMac reports 6 available input channels, which of course carries through to Reaper.

Can anyone tell me why?

[bazzbass]

Hi, not familiar with that interface, but I have a couple of thoughts.

Are the two SPDIF channels stereo ? that would make 4 inputs

Maybe the interface considers the combo jacks as two seperate inputs, ie the TRS is ch1 the XLR on the same socket is ch2 etc

I'm clutching at straws here

[JapanAxe]

The combo jacks are 1L and 2R.

3L and 4-R come in as SPDIF on a single phono socket.



So no!

I was transferring in some digital recordings via SPDIF last night, and when I selected channels 5 an 6 as inputs there was no signal. (I wondered whether 5/6 was a 'copy' of 3/4.)

[JapanAxe]

Mystery solved. Inputs 5 and 6 actually refer to the unit's 'Loopback' function, which allows you to send the signal that's being sent to your audio outputs [i]back[/i] into the input for recording. This is perfect for capturing streamed internet broadcasts etc. For example, if I play a YouTube video and set Reaper to record via inputs 5 and 6, the audio is recorded into Reaper. Previously I had to use Soundflower to do this, which meant switching back and forth between settings in the Audio Devices dialog box. I have now ditched Soundflower (it is no longer supported anyway) as this is a much more elegant solution.

Win win!

[bazzbass]

ahh glad you sorted it out

[JapanAxe]

[quote name='bazztard' timestamp='1482909357' post='3203400']
ahh glad you sorted it out
[/quote]

Me too! Nowhere in Roland's literature does it explain exactly how this works. Here's their signal flow diagram:



Incidentally, I've just tried recording bass direct using the Hi-Z facilit, plus the compressor accessible from the Quad Capture's dialog box. Unexpectedly brilliant!

[BigRedX]

[quote name='JapanAxe' timestamp='1482706784' post='3202305']
Mystery solved. Inputs 5 and 6 actually refer to the unit's 'Loopback' function, which allows you to send the signal that's being sent to your audio outputs [i]back[/i] into the input for recording. This is perfect for capturing streamed internet broadcasts etc. For example, if I play a YouTube video and set Reaper to record via inputs 5 and 6, the audio is recorded into Reaper. Previously I had to use Soundflower to do this, which meant switching back and forth between settings in the Audio Devices dialog box. I have now ditched Soundflower (it is no longer supported anyway) as this is a much more elegant solution.

Win win!
[/quote]

That seems like a bit of a faff, when you could simply use Audio HiJack to save the output of any audio stream from any application as a file.

[JapanAxe]

[quote name='BigRedX' timestamp='1483180741' post='3205212']
That seems like a bit of a faff, when you could simply use Audio HiJack to save the output of any audio stream from any application as a file.
[/quote]

Ooh! Downloaded!