アルファレコード
Alfa Records, YMO's record company, had installed a 3M 32-track digital recorder in its studio shortly before YMO started recording "BGM". Since Hosono was not fond of its overly sharp sound quality, he recorded all the rhythm sections for "BGM" on a TASCAM 80-8 analog recorder first and copied them with the 3M machine, resulting in the fuller, much compressed rhythm tracks. Unfortunately, no known working samples of the 3M recorder exist in Japan today, making it quite difficult to play the master tape.