The above posts pretty much cover it.

Have multiple inputs available hardware wise.
Enable them in the Prefs area for enabled input Ports under Audio-Drivers button
Record. RB lays them out on the next available track after the one selected. You only need to select one blank track to record to; RB just writes the rest to the next available blank track.

8-16 is done pretty commonly here.
In the image below I have selected 4 stereo channels to record to (essentially 8 Mono tracks) and line 3/4 out to monitor on..

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Last edited by rharv; 07/08/15 01:45 PM.
I do not work here, but the benefits are still awesome
Make your sound your own!