A semi-modular monophonic synth from Roland , manufactured from 1975 to about 1980, and not to be confused with the System 100m , which appeared later. The System 100 was a somewhat unique concept, as it consisted of a base unit and four optional components.
- The Model 101 is the base unit. It is a monophonic synth including a single VCO, a low pass VCF, a non-voltage-controlled high pass filter, a noise generator, a VCA, an envelope generator and a LFO. It includes a three-octave keyboard, but no pitch wheel or other performance controls.
- The Model 102 expander replicates most of the circuitry of the 101, sans the keyboard. It adds a sample and hold circuit and a ring modulator.
- The Model 103 is a four-input stereo mixer. It includes an effects loop and built-in spring reverb.
- The Model 104 is an analog sequencer with 2 rows of 12 steps each.
- The Model 109 is a pair of self-powered monitor speakers.
The Model 101 and 102 contain a number of internal normalled connections, which can be overriden by inserting patch cords. There are no normalled connections between the components, so all connections between components must be made using patch cords.
The System 100's voice archtecture served as the architectural basis for many of the synths that Roland would produce through the rest of the 1970s and on into the early 1980s. Parts of the circuitry design were re-used in several later models including the SH-7 and the aforementioned System 100m.