Thank you for the great responses @terrybritton and @cdv_gabriel !
As I said, I know that Cantabile has recording functionality built-in, but I want to add tracks to an existing multi-track recording. In fact I tried the C3 recording approach first, but had difficulty trying to sync my recording to the original recording when importing into the DAW. The recording to which I am trying to add tracks, does not have a click track or any other time codes - it’s a real-time recording. In addition, even when I was able to line up the beginning of my recording with the start of the original track I found that the recording did not maintain the sync through out the song (perhaps it was my playing?). Perhaps the suggested approaches of using Cantabile recording would work better if there was a sync signal in the original recording.
Due to the sync issues I thought I would try and record using a DAW. I thought that rather than sending the audio out (D/A conversion) from C3 into another DAW system (A/D conversion) using physical cables, it seemed that it should be possible to use a virtual audio cable to capture the recording directly into the DAW on the same machine as C3. Yes, I understand that CPU performance may be an issue, but a number of people reported about the low overhead of Reaper, so I thought it would be worth a try on my system.
I considered creating a new topic, but since I found this topic by searching for ‘Virtual Audio Cable’, I thought others would also find it here. In addition, I want to know about ‘Jack’, but unfortunately the video doesn’t seem to be available. @terrybritton can you confirm whether you are able to see the video?