Electro-Harmonix Stereo Talking Machine Vocal Formant Filter Pedal (Demo by Bill Ruppert) - YouTube
Buffer+ Stereo – Empress Effects Inc.
GFI System Skylar Mono/Stereo Reverb Pedal | Vision Guitar
Guitar Pedal X - GPX Blog - Old Blood Noise Endeavors's ingenious Float Dual Moving Parallel Stereo Filter takes the Filter Pedal Format to new heights
MATRIXSYNTH: Electrix Filter Queen analog factory stereo pedal
Old Blood Noise Float Dual Filter Effect Pedal
Resotron - Pigtronix
Source Audio One Series Spectrum Intelligent Filter Pedal | Murphy's Music | Instruments | Lessons | Melville
Guitar Pedal X - GPX Blog - Old Blood Noise Endeavors's ingenious Float Dual Moving Parallel Stereo Filter takes the Filter Pedal Format to new heights