The FX25 was initially produced by DOD in the early 80s and is an OTA-based envelope filter/auto-wa… | Diy guitar pedal, Guitar distortion pedal, Guitar pedals
Guitar Pedal X - GPX Blog - 12 of the Best Envelope Filter Pedals - 2018 Edition
How hard would it be to build an envelope follower? - Shruthi - Mutable Instruments' community
AMZ-FX Guitar Effects Blog » Blog Archive Dr. Quack Envelope Filter mods - AMZ-FX Guitar Effects Blog
FilterFX – 12dB/oct LP/BP/HP LFO filter with 8 waveshapes – Electric Druid