For anyone interested in musical box disc interchangeability, I have
put together a listing of those manufacturers and sizes which I am
aware of currently.  Please feel free to add or correct as appropriate.

Please note that I am excluding those which require mechanical
modification for cross-play i.e., the 20-1/2" Criterion & Olympia which
have different spindle hole diameters.

  19-5/8" Polyphon & Euphonion
  15-1/2" Regina & Polyphon
  15-1/2" Polyphon & Fortuna
  12"     Symphonion & Monopol
   9"     Britannia & Imperial
  7-5/8"  Symphonion & Edelweiss

Alan Fox
Santa Barbara, Calif.