sequencer

Analog synthesizers of the early 1970s often included a "sequencer" capable of cycling through a timed sequence of 16 different voltages (which would most commonly be used to control the pitch of an oscillator). This likely explains why so many fast 16-note repeating patterns appeared in electronic music of that time period. Most voltage sequencers allowed the user to set the voltage for each step of the sequence, and to adjust the timing interval (rate) of the sequence.