Synth DB

The Ultimate Synthesizer Database


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Yamaha | CS40m


The CS-40m is a duophonic (2-voice) analog synthesizer that was introduced in 1979. Although Yamaha had already conquered polyphony with their legendary 8-voice CS-80, the CS-40m offered a more affordable approach to something other than a mono-synth. It has a semi-compact 44 note (3 1/2 octave) keyboard, 36 knobs, 12 sliders and over a dozen buttons for easy hands-on performance and editing. There are also 20 patches of memory which can be off-loaded to cassette tape.

The CS-40m certainly isn't as phatt as the CS-80. In fact, the CS-40m is more like a 2-voice version of the CS-20m. Like most CS-series synths the CS-40m has two analog oscillators per voice. Triangle, sawtooth, and square (pulse) waveforms are available on each oscillator, plus there is a noise generator. There is also a simple AR (attack/release) envelope generator for each VCO.

The CS-40m has a multi-mode VCF (filter) switchable between lowpass, bandpass, and highpass filtering. Basic filter cutoff and resonance controls are here, but the filter's resonance can't be driven to self-oscillate. It does, however, have its own ADSR envelope generator for nice sweeping filter effects. There is a basic LFO (Low Frequency Modulator) for modulating the VCO, VCF or VCA. All these classic controls and features and sounds... you would expect wood panels... and there are! 

Engine TypeAnalog
Voices (max)2
LFOsine, up-ramp, down-ramp, square, and sample-and-hold.
Engine Detailed2 VCO's + noise gen. Triangle, Sawtooth, Square (Pulse) waveforms.
Filter (VCF)Multimode: Low-, Band-, High-Pass w/ cutoff, resonance, and ADSR envelope controls
Envelope (VCA)ADSR (x5 switch)
Memory20 patches via 2 banks of 10 presets; external cassette interface
Key typeKeys
CV-gateCV/Trigger out x2, CV in for portamento, sustain, brilliance, volume and filter.
Produced:1979 - 1986
Legend: Obvious Y: Yes, N: No, N/A: Not Applicable
VCO Voltage Controlled Oscillator DCO Digital Controlled Oscillator
LFO Low Frequency Oscillator Sub Sub Oscillator
VCF Voltage Controlled Filter VCA Voltage Controlled Amplifier
Velocity As with a piano, the harder you hit a key, the louder the sound, unlike most organs which always produce the same loudness no matter how hard you hit a key. Aftertouch Pressing a key after you activated it. Channel Aftertouch, no matter which key, it will send a Channel message. Poly Aftertouch, sends the pressure per key instead of the whole channel.
Values for OSC, LFO, Filter, Envelope are per voice unless stated otherwise.

Manuals, patches etc.


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