Back in 1979, this beast brought programmable memory to Yamaha's compact CS series, letting you save and recall eight custom patches on the fly—pretty forward-thinking for an analog monosynth era dominated by tweak-and-forget designs.
It packs dual VCOs pumping out triangle, sawtooth, pulse (with 50-90% width tweak), and a bonus sine in the VCA section, plus noise for grit; both oscillators detune smoothly across 64' to 2' ranges. A resonant multi-mode filter switches between low-pass, high-pass, and band-pass, paired with dedicated ADSR envelopes for filter and amp shaping. One versatile LFO offers sine, saw (up/down), square, or sample-and-hold waveforms for mod duties, with pitch and mod wheels handling bends (octave/fifth/third) and destinations like VCO, VCF, or both. The 37-note keyboard sits under a hefty black panel loaded with yellow preset knobs (for savable parameters) and white sliders for pitch, PWM, glide, and volume; CV/gate I/O and sustain/portamento switches make it modular-friendly. At 849x456x177mm and 16kg, it's a bulky, roadworthy tank made in Japan.
Players love its thick basses, searing leads, and bubbly effects that cut through mixes even today, though the single LFO and non-saving white controls draw occasional gripes from patch tweakers. Battery-backed memory keeps your sounds safe, and with proper care, it holds up as a raw analog workhorse.
