EQ Development Pack

Project overview

Have you ever wonder how it will be an Acapulco gold with extended EQ? or how nice it would be a Tube screamer with an active EQ section? Maybe Wampler Plexi with the Eq Section of the Freeman Be-od to make your own ultimate plexi? Well, now all of that is possible with our new EQ pack, consisting of 5 modular boards with the isolated tone controls of some of the most famous pedals out there.

We created the EQ packs answering our need of creating and developing new projects. This set of 5 different EQ sections had been designed with the idea of being an add-on to any of the pedals that lacks a tone stack or that has one that you don’t feel it takes the best out of your unite.

Our ultimate goal is to allow YOU to create your own designs, mixing and experimenting with classic effects, with one knob fuzzes, and more!

Important! You should be able to read schematics to fully understand how and where to add these EQs in the best possible way.

Introduction

This pack includes five of the most versatile and useful tone stacks in order to fulfill all your needs and to cover the whole spectrum of possibilities.

Hybrid EQ: Based on the EQ section of the REVV G3 and G4 present on our Revolution III and IV. Combines a Baxandall section for the bass and treble frequencies with an active mid control section.

In this project, we have included a Volume trim pot instead of the vol pot on the Revv. This could be bypassed, or you can connect an external pot through the numeric PADS (1, 2/OUT, 3)

Active EQ: Based on the Freeman BE-OD and the Dirty Shirley EQ section. We consider this EQ the best fit for Preamp emulator projects and high gain pedals.

Certainly the most complex of the pack. Includes an internal Presence control, followed by  Character trimpot that regulates how a set of LEDs compress the signal. Then we jump into a passive treble control, followed by an Active Bass section. Now’s when you have to choose if you want to have a volume control of the overall circuit inserted here from your main PCB board (Tube screamer, Plexi, etc) or to place just an internal trimmer as an additional control. After this volume section, it comes the active mids control.

One of the characteristic that makes this board the best solution for preamps and high output circuits it’s the Power output option, this works the best for those high output preamps to go and feed directly into a power amp, and the regular output will be tamed into a more pedal-friendly volume. If you are using this board with a pedal that’s not famous for his big output (Klon centaur for example) you should use the power output.

Amp Tone stack + Gain recovery: This Tone section is more focused on the ones that prefer a more classic and amp alike approach on their builds.

Recreates the 3 bands tone stack in the same way as it’s on tube amplifier and on many other famous amp in a box pedals (Catalinbread dirty little secret). This board allows you to experiment with different values in order to get different tone responses based on many classic amps.

Following the tone section, we have an external Presence control that follows the same amp a like logic. As usually, this tone stacks suck a lot of volume and gain, we have included at last one gain recovery stage. If you want to go with a more vintage approach you can easily bypass this last section.

Falcon EQ: Based on EQD Talons tone section. Advertised as an active EQ by the people from Akron, Ohio this EQ acts as a booster of the selected frequencies above twelve o’clock.

Includes an external Presence control that goes before the 3 band tone stack.

Benzin EQ: Based on the tone control of the Diezel VH4, this is definitely the one with more knobs, the one that will make tweakholics and high fans fall in love as equal!

At first, it might look pretty similar to the Amp Tone stack + Gain recovery, as the first section looks pretty similar. Both start with the 3 band Amp tone stack and the Gain recovery stage. However, the first difference is the Presence control, located after the gain recovery stage and bounded with the Deep Control.

This design also includes the possibility of having two simultaneous outputs as the Active EQ, featuring the same type of power output and tame output.

Important! You should be able to read schematics to fully understand how and where to add these EQs in the best possible way.

How to use them: there are many different ways of using these EQ boards, for example, if you want to use them with our Preamp sections based on Bajaman designs you can simply add them after the preamp section, like if it was another pedal in series. The same principle applies with fuzzes or drives that lacks of a tone control section. You can even try them even before the main Effect.

For that purpose, we even recommend boxing the Eqs as if they were normal pedals so you can plug them and compare them easily.

However if you want to insert this EQS as a replacement for a pedal that already has a Tone control, like a TS 808, KoT, Klon, etc, you should be able to read schematics and spot which is the best part to place them and which parts of the original circuit you should remove. Any doubt you have about this could be answered on our Facebook group PCB Guitar Mania – Builders Group.

EQ Development tool – Building Docs