Mini-moog. Ouch. That was my second guess. Yah, I've used reel-to-reel in similar ways. Also dubbed one effect on to a used cassette, with levels run up to solid red, for the "crunch" it gave. Also once dubbed over a pristine digital we were using to simulate an old Victrola, and put my thumb on the flange of the 10" reel for the wobble effect. Combined that with endless-tape loop of the guard tracks on a nicely scratched-up LP. All my collection of choral sounds is A) JV80 cards, B) old S-550 samples, C) tapes I made of our 80-member community chorus (which I don't have right to re-distribute). I've used the first two in designs before, but always hidden deep in the mix! :(