This thread is filled with misinformation. I posted about this several months ago, but nobody responded.
Next, the 1995 reissue of Who's Next had several songs from the album remixed:
Love Ain't For Keeping
Behind Blue Eyes
The remaining 4 tracks (Bargain, Song Is Over, Getting In Tune, Won't Get Fooled Again) were taken from copies of the original stereo mixes, as the multitrack masters could not be found. The multitrack for WGFA was later found and used for My Generation: The Very Best of the Who in 1996. The remaining 3 multitracks have (to my knowledge) not been discovered, and a few years ago Matt Kent made a post on Pete's website asking if anyone had seen them. So those are the 3 that are missing.
You are partially correct about Baba. While I haven't heard the tape myself, from what I can gather the organ backing track (yes, it's actually an organ, not a synth) is recorded on 2 tracks, and 2 more tracks are devoted to the "live" backing, comprised of drums (recorded in stereo), the piano (taken from Pete's demo, as was the organ), bass and guitar. That leaves 4 more tracks (as this was apparently an 8-track recording) for vocals, violin, etc. So while there *are* discrete tracks available, the drums, bass and guitar are apparently locked together. In theory you *could* use this for only singing.
Also, FYI, I don't think The Who's version of WGFA is played isolated on the DVD, just Pete's demo. Of course, the acoustic guitar and synth were carried over from Pete's demo to the Who's version.
1 - organ left
2 - organ right
3 - "backing" left (piano from demo, drums left and bass)
4 - "backing" right (drums right, bass, guitar)
5 - vocal (center)
6 - violin (center)
7 - lead guitar (center)
8 - ?
Pretty strange that Glyn Johns recorded all those things across two tracks, but I suppose just as strange is that they were recording on 8-track instead of 16-track. Perhaps it was so Pete could take the tapes to his studio (which was 8-track at the time).
FYI, from what I've seen, Rock Band seems to use this format:
- 2 tracks for "drums" (could be stereo drums, or a mono drum track spread across 2 tracks)
- 1 track for "bass"
- 2 tracks for "guitar" (not sure why 2 are used). This isn't necessarily a singular guitar part, but may have elements from several tracks flown in and out depending on what is "important" at the part of the song
- 2 tracks for "vocal" (again, not sure why 2 are used)
- 2 tracks for "backing" (basically anything that won't get muted during gameplay)
- other tracks for game effect (such as the "audience" in Won't Get Fooled Again)