Back in 1974, this synth pioneered additive synthesis in a compact monosynth package, letting you blend octave sliders like stacking harmonic layers for sounds that punch way above a single oscillator.
Its voltage-controlled oscillator feeds five sliders covering 32' to 2' ranges, each with switches for sawtooth, pulse, or square waves, plus pink/white noise that routes to the filter or amp. A resonant 4-pole low-pass filter shapes tones with cutoff and peak controls, modulated by two LFOs—one sine/square/random for vibrato, tremolo, or growl—and a single ADSR envelope handling pitch, filter, and amp. The wild sample-and-hold stands out, with random or semi-random modes that scale notes up/down at variable speeds via a dedicated LFO, alongside portamento, transpose switch, and an 8' chorus pot for subtle pulse-width movement. Housed in a rugged Tolex-covered wood case with metal corners, it packs a 44-note F-scale keyboard (about 3.5 octaves) and sheet music stand, outputting mono audio—all controls clustered left for easy piano-top stacking.
Players love its warm, meaty leads and basses that echo the pricier SH-5, with that early Roland character shining through on well-preserved units, though some note filter variations across production runs.
