VCA

Maker	Marten Agren
Type	Dual OTA VCA with switchable linear and exponential response
Mounting	Mixed
Width	—
License	Open source (MIT over a hardware-only repo)
Difficulty	🔥 SMD (0805)

Clone of Inspired by the RJWSoft Dual Log/Linear VCA. Uses the OTA diode bias inputs and adjusted supplies so both linear and exponential modes reach true zero. The README gives a three step trimmer calibration procedure. A separate UI board and a panel DXF are included.

Documentation

• Assembly instructions
• Bill of materials (BOM)
• Schematic
• Fabrication files (PCBA-ready)

Links

• Source / files on GitHub
• Maker page

More from Marten Agren

Waves CORDIC accelerated digital VCO on an STM32 Kick-808 Analog bass drum voice based on the TR-808 kick circuit Mixer Four channel Eurorack audio and CV mixer EuroPower Regulated Eurorack power bus board with ten module headers Resonator Digital resonator voice with quad CV inputs and stereo audio IO Beats Programmable clock sequencer with multiple gate outputs SteinerVCF Steiner-Parker style multimode diode ladder filter VCF Analog voltage controlled filter board

More vca modules

Streams Mutable Instruments Blinds Mutable Instruments Veils Mutable Instruments Dual VCA diysynth VCAs Super Synthesis TVCA Super Synthesis Segue Nonlinear Circuits EDU VCA Erica Synths

This is a third-party open-source design, listed here as a build reference. Specs are researched from public sources; check the source repo and store for the current BOM, panel, and revision before ordering parts. Corrections welcome.

← Back to all builds Resources Suggest a correction or a missing module