$25     Threeler Third-Order MultiMode VCF PCB


$55     Component Kit


.pdf Docs emailed with purchase of PCB

Unusual Parts you will need:

5 OPA2134

2 CA3280

OPA134

2 DG409

2K TempCo

2SA798

2 7.5V Zener Diodes

3 220pF Polystyrene Caps

2 10uF Tantalum Caps


A mighty and flexible filter, capable of Korg MS-20 sounds and a whole lot more!

A sound sample of the Threeler in action, controlled by Scott Stites and his Klee Sequencer.


The four 100k linear board-mounted pots can be Spectrol .1” spacing or Alpha .2” spacing, which are not available at Mouser, but we have them here.


Board Size 2.75” x 5.75”