Man, that's interesting. I've never used BiaB that way. Cool. Do you use the Chord Wizard?
Not the Audio Chord Wizard, its MIDI counterpart. I use
MIDI Guitar in Logic to pitch-analyze audio into MIDI, then I feed the MIDI into BIAB for chord analysis.
Here's the whole sordid process, if you're at all interested (and I greatly appreciate the interest you've already shown!) Starting with Dorothy's old record:
1) In Izotope RX9, separate voice from instruments to create two audio files.
2) In Logic, use
MIDI Guitar polyphonic pitch-recognition to create one MIDI track from vocal audio, and one MIDI track from instrumental audio, and export to a MIDI file.
3) In BIAB, import that MIDI file and perform chord analysis.
4) In BIAB, set up a RealTracks arrangement and export the song as audio tracks.
5) In Logic, import these BIAB audio tracks.
At this point, in Logic, I have (A) the original audio after "stem separation", (B) MIDI tracks from pitch-recognition of that audio, and (C) RealTracks from BIAB. I can now go to town with a snoot full of plugins and editing tools. In the end I used Izotope VocalSynth on the isolated voice, LABS Organic Textures
Thunder and Birdsong to render the MIDI, added a few stray MIDI winds, and set it down upon the RealTrack bass.
Weird With a Beard, and Fine As Wine. =8^)