This is the portable version of the later series of Moog modular systems. They featured the more stable 921 oscillators. Modules in the Synthesizer 15 included:
(2) VCOs - (1) 921, (1) 921B, with a 921B driver
(2) 902 VCAs
(1) 904A VCF
(1) 907A fixed filter bank
(1) 910 power supply
(2) 911 ADSR envelope generator
(1) 923 noise/high-pass/low-pass filter
(1) 952 49-note (C-C) duophonic keyboard
(1) 995 attenuators
(1) CP3 mixer control panel
(1) CP4A control panel with CV/trigger outputs and attenuators
[from The A-Z of Analogue Synthesizers, by Peter Forrest, published by Susurreal Publishing, Devon, England, copyright 1994 Peter Forrest]
