CubuSynth - Dual CS-20 VCF (DIY)

Dual / Stereo Multimode VCF with Self-oscillating Resonance and intuitive Routing and CV modulation Matrix

The CubuSynth Dual CS-20 VCF is a dual / stereo multimode VCF / Phaser / VCO, inspired by the legendary Korg MS-20, with CV control over frequency and resonance. The resonance can self-oscillate and features a 1V/Oct input, stable over at least 2~3 octaves.

Each of the two filter cores has 2 stages of Low Pass and High Pass filtering, which can be blended.

The Frequency CV can be “attenuverted” (with inverting attenuator on CV input). The resonance CV comes with an attenuator.

DIY version of the CubuSynth VCFA

Difficulty Level: 6/10
Build Time: 3 ~ 6 hours
Two PCB-Sandwich, normal component count, easy to solder & assemble
Component count: 172

Key features

- 2 individual Filter cores with common Frequency and Resonance controls
- CV control over Frequency and Resonance for each Filter core
- self-oscillating Resonance with LED feedback circuit (visible on the Front)
- 1 V/oct input, tracking over 2~3 octaves
- Frequency Range: 22 Hz – 20 kHz
- Blend between LP / HP Filter modes
- Ability to use as 2 pole (12db) stereo HP/LP Filter, 4 pole (24db) mono LP/HP or a Band Pass (12db) Filter
- Cross FM Modulation possible

Specifications

- Size: 10HP x 3U / 50mm x 129mm
- Depth: 24mm (measured from the front panel)
- Max. Current Draw:
+12V: +19mA
-12V: -19mA

 Modulargrid

PCB+Panel pack contains:

- Main PCB
- Control PCB
- Front Panel

The Full DIY contains all components and PCBs to build the Module