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The ED104 comprises 2 LIN/LOG VCAs with additional VC Panning function.


In July 2002, EDN Network published an article by Mike Irwin on the application of op-amps to linearise the response of a voltage controlled attenuator built around the Analog Devices SSM2164.


In September 2003 Phillip Gallo published a design for a Dual LIN/LOG VCA utilizing this design idea and the ED104 realises that design in a euro-synth module.


Although the ED104 has two separate VCA’s, the [LIN/LOG] control law is switched simultaneously for both VCAs so that they both operate with the same control response.


In stand-alone mode a control voltage is fed in to [CV x] while an audio signal is fed in to [AUDIO IN x] with the resultant output at [AUDIO OUT x].

With the CV level control at maximum, a 0V to 5V signal will raise the gain of the VCA from -100dB of attenuation to 0dB while increasing the voltage from 5V to 10V will further increase the gain from 0dB to +20dB.


For operation in Panner mode, a single audio signal is fed in to [PAN AUDIO] while the panning control voltage is fed in to [PAN CV]. The [CV A] and [CV B] level pots should initially be set to maximum




This Module is available to buy as - 


  • A fully assembled module with 3.5mm sockets. (Eurorack 1/8" Standard)
  • A fully assembled module with 4mm sockets. (Banana Jack)
  • A full DIY kit, all parts and components to build your own 3.5mm sockets.
  • A full DIY kit, all parts and components to build your own 4mm sockets




Width: 16hp

Depth: 70mm

Contents: Panel, PCB/s, Components, Ribbon Cable, Screws

Build and Technical Information: Click Here

Elby Designs ED104 Dual LIN/LOG VCA DIY KIT Eurorack Synthesizer

3.5mm or 4mm Jack
  • Shipping Transit.

    With Tracking 7-14 Business Days (Estimated)

  • Sales & Taxes.

    The sale price listed is AUD (Australian Dollar), and is the final price to pay.

  • Payment.

    Credit Card (Visa, Mastercard, Amex), PayPal.

  • Warranty/Returns.

    1-Year warranty against defects, and manufacturing faults. (Click for more)

  • Additional Notes.

    This module is available to buy with 3.5mm (1/8" Jack) sockets or 4mm (Banana Jack) sockets.