YuSynth VCO Modules

Should modular DIYing compare to a meal, the VCO is the main course ! It is the heart of the system, the module without which a system cannot be called a Music Synthesizer.

The design of such a module is not easy and building one with good accuracy, low drift and good thermal stability is not simple. Yves tried various architectures and eventually came up with quite a classical design.

Herein he propose, three different PCB designs that let the builder choose the solution that matches best his/her needs or budget.

  • The first design uses high grade components such as LM394 or SSM2210 chips for the dual transistor of the exponential converter and an OPA2137 low bias OPA for the voltage summer and servo OPA.
  • The second design uses a Japanese 2SC1583 dual transistor which is much cheaper. - Not yet available
  • The third design uses a pair of hand matched BC547B. - Not yet available