The old days are back...

Do you miss the old days when a synth was not plug n play, but a challange in routing? Where you had to tune a synth before you could play it and where spring reverbs and filters would go nuts?

With Cynthia you can do all that crazy stuff you cant do with a modern synth. Cynthia is monophonic VSTi, very Old School, but will still be able to keep in tune throughout the song, patches can be stored and it is of course fully MIDI controllable.

Cynthia is free to use and will send you 30 years back in time to the dawn of modular synthesis...

As the name implies its inspired from the old EMS SynthiA. I did my best to match the specifications of the SynthiA, but as I got bored I threw in a bit extra...

Latest build: v1.02
(Older versions?)

Stay tuned - be creative!



Latest news

older news...




Control voltage and sound sources
  • 3 monophonic oscillators with controls for shape and level of the waveforms, sync and phase-shift
    • OSC1: Range from 0.6 Hz to 16 kHz, sine and triangle
    • OSC2: Range from 0.6 Hz to 16 kHz, square and triangle
    • OSC3: Range from 0.015 Hz to 500 Hz, square and triangle
  • Noise generator
  • Two audio inputs so you can modify the sound of a guitar or your voice
  • 8 step control voltage sequencer
  • Attack-hold-decay(-repeat) envelope generator producing a control voltage with adjustable level and bias
  • A self-oscillating filter (can be used as a sine OSC as well)
  • 3 VCA's controlled by the envelope generator or control voltages assigned to the output level of each channel
  • Ring modulator
  • Spring reverb with short and long spring
  • Delay (delay time from 0 to 10 seconds)
  • Tuner for tuning OSC's by ear
  • Joystick for extra control
  • 16 x 20 routing matrix with inputs for host MIDI pitch and velocity and inversion of individual connections
  • MIDI cc's can be assigned to any knob
  • Adjustable portamento time
  • Trigger button for triggering the envelope generator
  • 2 pairs of stereo outputs with extra filters, pan and volume control
    • Direct out
    • Speaker (simulating the sound of a pair of canny speakers)

Press play to hear what Cynthia can do...

Shuffle Cynthia, Shuffle

Dolphins Talking

On the Cynthia

Guitar destroyer (unprocessed, then processed)

Installation is pretty easy. Unzip the files to your VST folder and load it in your host. Note that there are two files: A VST and a VSTi file - one for effects using the input channels and one that behaves like any other VSTi. There's also a manual included, that explains just about everything.

Please note that the synth is quite different from ordinary synths so it may behave unexpected at first. That's why I included a manual :-)

Otherwise please use the forum.

  • A PC with WinXP (haven't tested on Vista, but please try)
  • A host/sequencer. Its tested to work with Reaper, but most sequencers (Cubase, Sonar, etc.) will do fine I guess
  • A fast CPU - I recommend at least 1.5 GHz. Note that loading multiple instances of any VST made with SynthEdit can cause problems on a multicore system, so be aware of that!
  • I suggest to use ASIO drivers. If you didn't get these with your soundcard you can get some from


Made with SynthEdit

Presets labelled HS made by HSkovlund

Copyright info: You can use the pictures, info, manual etc. on this page as you want, but I would prefer that you refer to The synth it self is my creation, so please dont re-sell it or do any reverse engineering on it. Help me keep it free :-)

/Ninecows, 2008