Genzler re/Q Dual Function EQ Pedal | Bass Buddha
Amazon.com: Death By Audio Evil Filter Pedal : Everything Else
Pigtronix Introduces the Resotron Analog Filter Pedal – No Treble
DIGITECH Effektpedal, DOD Envelope Filter 440, Band Pass Filter Pedal - 24h Online Shop
Review - Broughton Audio: Josh Wah, Low+High Pass Filter, and Apex Compressor - Bass Musician Magazine, The Face of Bass
Pribor Pedals Envelope Filter F-7 Polivoks Low Pass Band Pass LP BP guitar bass pedal cv controlled | Reverb
Guitar Pedal X - GPX Blog - Preferred Filter Pedal Selection - at the key practical enclosure sizes
Bruel and Kjaer Model 1613 Bandpass Filters | Reverb UK
Genzler re/Q Dual Function EQ Pedal | Bass Buddha
bandpass filter in a stompbox - freestompboxes.org
The Different Sounds You Can Create With A Step Filter Guitar Effect – FuelRocks
Death By Audio Evil Filter Octave Fuzz I CME Gear Demo | Joel Bauman - YouTube
Dynamic Band Pass & Clipping Effects Pedal Circuit for Guitar : 3 Steps - Instructables
EVIL FILTER - Death By Audio
Variable Band-Pass Filter Questions - Gearspace.com
An Introduction to Envelope Filters | Hochstrasser Electronics
Vintage 1970's Original Mutron Inc. Mu-Tron III Envelope band pass Filter Pedal | eBay
Guitar Pedals: Gyrator Filter Calculator
operational amplifier - Band-pass op-amp structure with parallel diodes in feedback? - Electrical Engineering Stack Exchange
Low + High Pass Filter | Broughton Audio
FG3 | Effectivy Wonder Pedals
Audio EQ: What Is A Low-Pass Filter & How Do LPFs Work? – My New Microphone
Automatic Wah/Quack Effect Using LED+LDR Controlled Band-Pass Filter – Deeptronic
I've wanted a passive octave bandpass filter like the Brüel & Kjær 1613 for a while, but found it difficult to source - so I designed and built my own in 10hp! :
