Yamaha CS-20m

Yamaha CS-20m Image

The CS-20m is another of Yamaha's classic CS-series analog synthesizers of the '70's and '80's. It is a monophonic analog synthesizer with dual-VCOs that use subtractive synthesis to create superb bass, synth, lead, bubbly-squirty and percussive sounds. It has all the essential components of a classic synth: There is a resonant filter with switchable high, band or lowpass filtering with its own ADSR envelope controls. There is an ADSR VCA envelope generator which contains a third oscillator which generates a sine wave to modulate and enhance your sounds. And there is an LFO which can modulate the PWM sweep. Fortunately, the CS-20m features 8 memory locations for patch storage of your favorite or most used sounds.

Stacked up against the other CS-synths, the CS-20m appears to be a very little brother to the CS-70m (a 12-VCO and very flexible beast). The CS-20m offers more memory patches than any other CS-synth (excluding newer CS1x and CS6x models). As for other synths, the CS-20m could be considered Minimoog-like, though it sounds much brighter and thinner than the Mini. If the Minimoog's price is out of your league, the CS-20m is not just a nice alternative but it is quite a classic and solid analog synth! It is used by The Crystal Method.

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Are you looking to buy or sell a Yamaha CS-20m? Post an ad in Gear For Sale or a request in Gear Wanted. For spare parts and repair services check out Gear Services & Other Goods. Our forums also has a Buyer’s Guide section where you can ask for advice on buying synthesizers.

15 Visitor comments
Alain Vinet
September 10, 2013 @ 10:24 am
I own this sweet Synth but...unfortunately last week it smelled funny then stopped working altogether. I've done some testing with a multi meter and the Xfo doesn't seem to be outputing any voltage at all. My question here is : Does anyone here have a clue as to the different voltage outputs of this Xfo on the different colors (it has Red, Orange, Yellow and Blue wires plus the green which is mass)? Or perhaps someone has a detailed servicing schematics? If you have any clues for me, please write me : alainvinet@me.com
August 22, 2013 @ 7:41 am
Big, ballsy analogue bstard!!!! Sounds thick and creamy and at times, angry.
Don't make them like this any more....pure class.
Puts most if not all analogue wannabe's to shame.
The good thing is yer hardly hear these synths any more because they are expensive and ppl are hooked on all this virtual analogue garbage.
It ain't midi....SO!!! make a sound and sample it then use it.
Big analogue sound that is hard to replicate on virtual analogues.
Devin Jonas
February 1, 2013 @ 11:34 am
Hi guys, got the manual in PDF, however I am struggling to solve the puzzle that is te plug.

I need to put a new one on - Bought the plug - Forgot the fuse to go in the plug... Not that I know which is recquired.

Could anyone assist? Very much look forward to getting it up and running.

Best regards.
Bob Weigel
September 29, 2012 @ 5:05 am
actually there is no 'third oscillator'. The sine wave amount in the VCA section is simply a filter bypass of vco 1 you'll notice if you play with the controls. That's confusing at initial glance. It does allow you to thicken up the sound, particularly using bp or hp filter selections. That's why these are one of the great synth bass machines really.
July 30, 2012 @ 7:39 am
Hi - My friend has one of these and whilst fixing it has somehow lost the silver buttons/dials... do any of you know where/if you can get spare parts for this?
Thanks for any help
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User Rating

Rated 3.49 (292 Votes)

  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - Monophonic
  • Oscillators - 2 +1 sine osc. in VCA section
  • LFO - 1
  • Filter - 1 filter with low, band or hi pass; ADSR envelope
  • VCA - 1 ADSR; additional sine wave generator
  • Keyboard - 37 keys
  • Memory - 8 patches
  • Control - CV / Gate
  • Date Produced - 1979
  • Resources & Credits
  • Images from Dance Tech.

    Thanks to Scott Rogers for providing some information.

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