Synthesis Technology MOTM-485 GX-1 VCF

Courtesy of Paul Schreiber, here is the link to the Synthesis Technology User Guide: http://synthtech.com/motm/docs/MOTM485%20User's%20Guide.pdf

The MOTM-485 is a recreation of the Yamaha GX-1 LP/HP filter.

The GX-1 was a massive organ/synth hybrid, costing over $60,000 in the late ‘70s. The best example is the ELP song ‘Pirates’, but was also used by Stevie Wonder and Led Zepplin..

The actual GX-1 used a pair of these filters to form a bandpass response (the same method used in the MS-20 and the CS-80).
There is a HP filter set to "half tracking" followed by a LP at "full" tracking. However, you can still use a single MOTM-485 as yet another distinct tone in your setup.
 

Faithfully captures the unique GX-1 timbre

2 audio inputs

Voltage-controlled resonance

Switchable HP/LP response

Switchable half/full tracking of the 1V/Oct input

Fully temperature compensated using TEMPCO resistor and matched pairs

Not a ‘clean’ filter: has higher distortion than other MOTM filters

On Demand Info

These kits and assembled modules are offered on demand, click the link to learn more.