Proto Pedal Example: Analog Equalizer Project - SparkFun Learn
Simulating the Boss GE-7 Graphic Equalizer in LTSpice
Simple, Easy Parametric and Graphic EQ's, Plus Peaks and Notches
Build own EQ pedal???
Guitar FX Layouts: BYOC Parametric EQ
Guitar Pedal X - GPX Blog - A Brief Hobbyist Primer on Key Tone Stack Types and Circuit EQ Configurations - in collaboration with Master-Builder Adrian 'Thorpy' Thorpe