This website is targeted to the EU and USA only. If you want to buy the Subsonic filter module from another country then please contact me for the shipping cost.

What is it?
A subsonic filter is mostly used for piezo elements. Mechanical noise is typically induced when using palm muting techniques or a tremolo and this can produce annoying ghost notes. This is a six channel filter module that removes subsonic non-musical and mechanical noise from the output of a 13-pin divided pickup to improve synthesizer tracking and COSM modeling.

How to install?
You need to open up your GR-55 and insert it in-between the 13-pin DIN input plug and the board connector. It is very easy to install, just re-connect two connectors.

Schematic
You can also choose to build this yourself as this is an open source solution that is available on the internet. It is the same schematic as used in the GR300 Filter Buffer device. Or you can buy a similar subsonic filter available from RMC.