Need help with Muff diagram / Mojo Hand Colossus

[Tremster]

Dear forum,

I don't feel confident enough with my diagram reading skills, any help would be appreciated.
A friend asked me to build a Mojo Hand Colossus (=a variant of a Russian Muff with mids control and an input cap switch), he had an original years ago.
I can't find a PCB for it, but I have a Fuzzdog BMP board that should do fine: https://shop.pedalparts.co.uk/Big_Muff_Pi/p847124_20010593.aspx
The schematic is in the BOM on page 3: http://pedalparts.co.uk/docs/BMP2018.pdf

The Colossus schematic is on the Kit Rae Muff page: http://www.bigmuffpage.com/Big_Muff_Pi_versions_schematics_part4.html:



The question is (parts numbers are different):
How do I match this bit from the Kit Rae schematic

with this bit from the Fuzzdog schematic


Where does Kit Rae's C14 go on the PCB??
Kit Rae's C9 is parallel to the Mids pot, Fuzzdog's C10 is before the pot??
The Colossus uses much larger values around the Mids pot than other Muffs with a Mids pot (Musket, Hoof; see Fuzzdog doc for those). Is there something wrong?
This is beyond me, I'm sorry.

Thank you!!!!

Here's what I came up with matching the Kit Rae diagram with the Fuzzdog diagram for use on the PCB (The parts numbers are for the PCB, Kit Rae has different numbers). I think I have it all except for the parts around the Mids knob parts mentioned above:

R1 33k
R2 100k
R3 470k
R4 140R
R5 12k
R7 1k
R8 10k
R9 100k
R10 470k
R11 12k
R12 390R
R13 10k
R14 390R
R15 470k
R16 100k
R17 12k
R18 47k ??
R19 10k ??
R21 100k
R22 470k
R23 2k
R24 10k
R25 1M
(no R6 and R20 on PCB)

C1 10nF + 100nF/2u2 on switch
C2 470pF
C3 100nF
C4 100nF
C5 560pF
C6 47nF
C7 100nF
C8 560pF
C9 47nF
C10 22nF ??
C11 47nF ??
C12 100nF
C13 100nF
C14 100uF

D1-2/4-5 1N4148
D3&6 by choice
D7 1N4001

Q1-4 2N5088

Tone / Mids / Sustain 100kB
Volume 100kA

[Feral Feline]

You can't add Kit Rae's C14 to the Fuzzdog PCB directly.

The shift and mids knobs are not implemented the same way; as you noted : Col-C9/FD-C10 are positioned differently relative to the mids/shift pot in each schematic.

The way I see it, you have three options, each one building the Fuzzdog PCB up as close to Colossus spec as possible barring the tone-stack.

1) NON-COLOSSUS stick with the stock FuzzDog Tone stack. Colossally Colossus, but not the tone-stack.

2) SEMI-COLOSSUS same as above, but add Col-C14 between FD-PCB's SHIFT-1 and Tone-3

3) FULL-COLOSSUS — if you or your buddy is a stickler for accuracy, omit ALL FD bits  from (including) FD-C16 up to, but not including FD-C12.
You're now going to build the entire Colossus ToneStack off the backs of its two pots.

It's easier than it sounds/looks. Beavis Audio shows you how, http://beavisaudio.com/techpages/bigmufftonecontrol/. I'd mock up the pot spacing of your planned enclosure with a piece of cardboard, mount the pots in the cardboard, label them clearly, and start soldering in the Colossus bits:

COLLOSUS
C9 solder it between Mids-1 and Tone-3
R8 stretches from Mids-1 to Tone-1
R5 solder from Tone-3, leave the other end dangling.
C8 solder one end to Tone-1, leave the other end dangling or solder it to the R5-Dangle


Now you're ready to ditch the cardboard and wire it up in the enclosure.
Run a wire from the FD-C16 pad ( on the side that comes from the 2nd Clipping stage to the Mids-pot Lug 1.
Run a wire from the COL-R5/C8 danglers to a ground (suggest using whatever's most convenient close, be that the gnd pads of either the FD-PCB's C11/R18, right to the jack, one of the extra ground pads on the PCB.
Run a wire from POT Tone-2 to PCB TONE-2. 

DONE!...



...and I just saw an easier way to do it. The easiest. Hey, I'm sleep deprived at the moment, cut me some slack.

Basically, you just need to offboard wire the mids/shift pot, the Col-C14 and FD-R18 (Col-R5).

Except for the mids/shift pot and FD-R18 (COL-R5), install all the FUZZYDOGGY Tone-pot goodness.
1) Run a wire from between FD-C16 & FD-C10 to your mids/shift pot lug 1, jumper 1&2;
2) Solder COL-C14 to mids/shift pot lug 3 and leave the other end dangling.
3) Run a wire from Col-C14-Dangle to FD-PCB Tone-3; RUN Col-R5 (FD-R18) from Tone-3 to GND.

DONE.

GOOD LUCK Tremster!

And now some sleep for me...

[Tremster]

Whoa!
Thank you very much!

[Thewintersoldier]

When I built my musket fuzzes I used the Aion boards and then changed tone and mids control to the colossus specs and the rest of the circuit to either green russian or violet rams head specs. I much prefer the colossus tone stack to that of the musket and is easier to dial in.