With its lightweight plastic case, miniature keys and built-in speaker, you’d be forgiven for mistaking the CS01 for a toy. It was certainly a budget offering when it was released way back in 1982, but those unassuming looks hide a proper synth with a very big sound.
Despite its name hinting at a shared lineage with bigger synths like the CS15 and maybe even the CS80, the the CS01 is a much more humble offering, part of Yamaha’s Producer Series of budget along with the MR10 analogue drum machine and a selection of cheap and cheerful headphone amps, speakers, mixers and cassette recorders.
The CS01 uses a digital tone generator (oscillator), but the rest of the synth architecture is a classic analogue design: adjustable VCO, VCF, VCA and envelope generator sections, plus a basic sine wave LFO which can be used to modulate pitch or filter cutoff. The result is a simple but flexible setup which is a great introduction to sound design. Even a total beginner should be able to get some powerful bass sounds out of the CS01’s simple synth architecture.
The CS01 is also ripe for modification, with users adding connections for external CV input, variable filter resonance (later models included this as standard) and even MIDI control.
It may not be the most professional looking keyboard in the world, but the CS01 is a great introduction to the world of vintage synths. An unassuming little keyboard which packs a surprising punch.