Roland System 100

Introduced in 1975, the System 100 (not to be confused with the fully modular System 100M) was comprised of 5 sturdy components:

101 Synthesizer (single VCO with normalized routing and patch points)

102 Synthesizer expander (again, single VCO with normalized routing and patch points)

103 Mixer (4 into 2 with reverb)

104 Sequencer (12 x 2 or 1 x 24 CV sequencer with on-board clock)

109 Active loudspeakers

From the numbering of these modules it would appear that more were planned, but none were forthcoming.