Good job. These are hard to dig out
@effinRipper Do you happen to have a FLAC of Carl Matthews – East/West [Mirage M606]?
Unfortunately no. It was repressed in 2019 as a very limited CD so that might be your best chance to track it down.
Some speculation about the other ones:
#1 seems to be using Fairlight CMI samples, my guess is it samples something that was using Fairlight. Check Terminator 2 soundtrack, T1000 theme for reference. Intro looks like a radar screen on oscilloscope (stereo field rotation). Has high pitched TV whine at places (check Peter Gabriel demonstrates Fairlight on youtube).
#2 real head scratcher. Sources of sounds are all over the place but out of all versions of that song I could dig out I still have to hear anything used in this version so if anyone here has it please upload the rip so we can cross that out
https://www.discogs.com/release/18437908-Giovanni-Fenati-At-Piano-Per-Voi-Giovani#5 seems to be composed in the vein of Music of The Spheres which loops over itself a couple of times. Cassette release. Possibly samples a Nasa recording (my wild speculation according to some findings).
#6 short track but mysterious. Vinyl. No idea where to place it really, could be a weird interlude on some ECM LP or even a library record.
There is always a chance any of these is an original BOC track but this being SxT, a mixtape of their influences in which every track sounds like them is unlikely. Any ideas are welcome!