A device built by Alan Parsons as an analog sample playback device, similar in general concept to a Mellotron. The Projectron consisted of a24-track tape machine, with each playback channel routed to a voltage controlled amplifier; each VCA was in turn gated by a key of an attached keyboard. Parsons prepared a tape for the machine by recording a sound sample on a separate tape machine and making a loop of that tape, and then playing the loop for several minutes while recording the output on a channel on the Projectron's tape. After sustained sounds were thus transferred to all 24 of the Projectron's tape channels, the Projectron tape could then be played, and a melody (or set of sound effects, or whatever) played via the keyboard. Parsons used the device on the Alan Parsons Project's albums I Robot, Pyramid , and The Turn of a Friendly Card. But preparing tapes was a cumbersome process and the device was maintenance-intensive, so as soon as a Fairlight CMI became available to Parsons, he switched his sampling activities to that. Parsons scrapped the Projectron sometime after 1980, and no photos of it are known to have survived.
Other artists have employed similar techniques of recording looped sounds to a multi-track tape, and then "playing" melodies from the tape by manipulating a mixing console's faders while the tape plays. Lol Creme and Kevin Godley used such a technique to produce the backing vocals on the 10cc song "I'm Not In Love". Guitarist Steve Hackett and engineer John Acock took this a step further on Hackett's Please Don't Touch album, using a Neve console's automation system to produce backing vocals on several songs.