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Forum Home > Layout Gallery - GuitarPCB Build Documents, Mods and Tips > Big Muff Pi - MUFF'N - Fabricated Version

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Pre-2018 version of BMP MUFF'N at top.

For new 2018 MUFF'N version released  3/23/18  (scroll down)

Based on the original G.B.O.M. board by DCountry13

Pre 2018 version info:

Board Dimensions (W x H) 2.13” x 1.67” i.e.: 54.0mm x 42.4mm.

This design will fit into a 1290NS/1590B size enclosure or larger. We recommend a 125B enclosure or larger for beginners, and larger enclosures, e.g. 1590BB for those that want to add a lot of mod switches and knobs. This project replaces the GBOM - Ultimate Muff Project.

Beside this being a new fabricated version this circuit board was redesigned from the ground up with the beginner in mind. There will be (2) separate Build Documents.

1. One for the beginner wishing to build there favorite Muff style variant.

2. One for the more advanced builder wanting to incorporate as many Mods as they wish and I must say that with this new design even this will prove to be much easier.

From this Layout you may build anyone of these Muff related projects.

1. Rams Head

2. Violet Ram

3. Triangle

4. 3rd Edition

5. Creamy Dreamer

6. Foxy Lady

7. Green Russian

8. Black Russian

9. Civil War

10. Mayo

Not to mention many mods you may use with any of the above builds so that you may customize your favorite version your own special way.

Watch the Video:

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Build instructions for all MUFF'N builds. Written with the beginner in mind. 

Check the Forum for answers to many questions before posting a troubleshoot thread.

Do not miss the Easy Pedal Wiring Guide.

Namely the expansive Tips, Tricks and Tutorials section and the consolidated Crash Course Guide.

Picture below contains all mods to the standard build. Intended for advanced builders.

Scroll down for the new 2018 V3 MUFF'N Build section.

Pre-2018 Big Muff Pi - MUFF'N Board

Here is a Finished Build thread:

A Muff'n combo with a Hot Chilicon:

Here are (2) excellent Big Muff Pi resource sites to help aid in your personal selection:

In regards to the Omitted Pad... how about an 11th Muff variant!

Ask and you shall receive...


R23 -6k8

R24 -2k

C14 - 10uF

Then additionally make these changes:

R2 -39k

R3 - 47k

R6 - 10k

R8 - 8k2

R13 -6k8

By doing this you have yourself a very Firey Red style Muff.

Here is a very old audio demo I did while testing the circuit (Single Open Air Microphone 10' ft.)

We always encourage a "socket and see" approach so if you want to try experiment with something different and you like it feel free to report back to us your findings. Maybe we will make a mod named after you?

Another interesting Mod is to add the Tone TwEQ 3 Band Active EQ to your build:

Here are some Tone TwEQ'd builds by Trom:

Here is an excellent Muff'n Build Journal w/ all mods including RotoTone:

MUFF'N build journal featuring all mods Courtesy of Cybercow


New 2018 V3 MUFF'N includes advanced Mods

New slimmer width 1.95" x 1.84"

Build Document - Released 3/23/2018

The immediate advantages of our new 2018 - BMP MUFF’N include a slimmer 1.95” width with a familiar triangle potentiometer layout and Tone Control properly located in the center of the board.

Component layout is reorganized to offer the best Muff Style circuit w/ 7 optional Modifications in such a small board.

One easy mod, available in every “standard build” is a switch for the clipping section, which allows you to switch between “stock” silicon diodes, LED’s, or disable clipping in that gain section completely. If you want a “stock muff” without selectable clipping, the wiring diagram below on page 2 describes how to exclude it.

Enjoy up to five advanced “On-Board” modifications which this board was specifically designed to accommodate. We strongly recommend that all builders start first with a tested and working, “standard build” before any additional modifications are added. This equals a total of 6 modifications on a single board if you wish.

Build the Ultimate MUFF’N by adding on a Tone TwEQ giving it an Active 3 Band EQ.

That would be an awesome and easy 7th possible Mod bypassing the simple BMP Tonestack.

Attach Tone TweQ between J3 and J4. Open jumper J1. Discard all components between J3 and J4 or simply ignore them. The Volume on Tone TwEQ can be a fine tuning 100k trimmer, additonal on-board pot or bypassed by attaching to pad 3. Right click and Save as (PC) for larger view.

Here is a sample using three different circuits showing how to "inject" the Tone TwEQ into the Main Board while at the same time eliminating the main board's basic tone stack:


Template for 2018 V3 Courtesy of PedalPartsandKits USA:

November 28, 2012 at 12:43 AM Flag Quote & Reply

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