Author Topic: Changing frequency filter caps…  (Read 1801 times)

jessenator

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Changing frequency filter caps…
« on: June 16, 2022, 12:26:30 PM »
SO, I'm interesting in tinkering with modifying the filtration of the Super-Fuzz circuit and wondering a few things:

Are these two caps the main ones? From what I've searched, the filter is a bandpass, essentially making it a mid-scoop filter (at least it sounds like Metallica when I switch it on :P )

If I was to omit one of the caps, simply jumpering it, would I make it into a low/high pass depending on the values of the caps?

Could I modify it into more of a notch filter, where I'm boosting mids vs cutting them?

I'm pretty sold on the idea of replacing the switch with a pot to give more tonal control also, but generally I LIKE the circuit, I just don't like mid scooping, personally.


thanks

edit: I just realized this is my bad schematic lol. Yeah, the barrel jack for power has the poles swapped :|  just ignore that, I'll have to get a new board, I know, but just forgot about it.

edit 2: yeah, there's lots wrong with this schematic… it was my first, though. I hadn't figured out how to mirror drawings :S
« Last Edit: June 16, 2022, 12:35:14 PM by jessenator »

jwin615

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Re: Changing frequency filter caps…
« Reply #1 on: August 31, 2022, 07:02:44 PM »
To my eyes, looks like a modded bmp tone stack.
R24 c14 are low pass
C15, r23 are high pass
You should be able to modify.
See Duncan tone stack calc
You could do a pseudo mids knob hack and add a variable resistor (trimpot)in place/series of r23 and tune by ear. That would be a fast and easy experiment.
Maybe change r22 to 2k and add a 20k trimpot(or pot).
Or tie two legs of a pot together with a resistor (equaling ~44k combined, 22k ) and replace the resistor with that.
May have to modify the corner freq of the other filter stage though.
Give this one a readover.
https://www.coda-effects.com/p/big-muff-tonestack-dealing-with-mids.html?m=1

jessenator

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jwin615

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Re: Changing frequency filter caps…
« Reply #3 on: September 01, 2022, 05:11:29 PM »
I think Wampler did a good yt vid on the bmp tone stack mids mod. Or maybe diyguitarpedala did. Or maybe both.