Mod Boss FV-500-L/FV-500-H Expression Output for use with Line6 Helix/HX Stomp

[Marshall Arts]

I don't know, if this has been described somewhere else, but I thought I'd share it. I wanted to use my Line6 HX Stomp with an existing volume pedal (Boss FV-500-L) and a momentary footswitch. To use the expression output of the volume pedal alone with the HX, no modifications are required, just make sure you use a TRS (stereo) cable (mono - TS - won't work). If you want to use an additional footswitch (which will show up as FS5 (!) in the HX) you need to get hold of the ring and the sleve of the TRS cable and connect a momentary footswitch. I found the easiest way to do it was to add a mono (TS) jack to the volume pedal and connect it to the jack PCB as shown.

Don't be irritated by the dc jack I also added to the pedal: I added a buffer to the pedal as well, but the mod for the HX is completely passive / does not require power.