4U – Setonix – Boing! (Discrete Transistor Low Pass Gate) pcb/panel/2 x LDR

£14.99 (exc VAT)

4U User’s Manual

4U Build Manual

4U Bill of Materials

4U Interactive BOM

This listing is for a 4U pcb/panel/2 x LDR. You need to source the other components for the build yourself.


In stock

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The Boing! is a Light Dependent Resistor-controlled low pass gate. It takes its primary inspiration from ultra-simple yet delightful passive Vactrol Low Pass Gate modules such as the PassiVac and DPLPG, but adds JFET transistor input and output stages and an active LED control circuit, thus enabling the introduction of wonderful Damping (negative feedback) and Trigger functions, LED brightness offset, and a second filter stage. Combined, these features allow for incredible variable-cutoff overdrive and all pass filter sounds in addition to bouncy LPG Bongos and more.

This module is a Loudest Warning-format 4U module with a width of 1”, consuming approx. 12mA of power on the +12V rail.

This panel/PCB set includes a bare panel, PCB, and two hand-rolled “vactrols” needed for the build. Due to the nature of DIY kits, we cannot accept returns that have been partially assembled.




Additional information

Weight 65 g
Dimensions 128.5 × 50 × 50 mm

Synthesiser parts/components

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