Big Muff Tone Control Frequencies

[rbruss82]

Referring to the the tone section of the Big Muff from http://www.generalguitargadgets.com/diagrams/bmpsc.gif

I'm seeing a low pass filter (39k and .01uF) that allows frequencies below 408Hz, and a high pass filter (100k and .0039uF) that allows frequencies above 408Hz.  Bottom line:  both filters have breakoff frequencies of 408Hz.  These frequencies are found by 1/(2*pi*R*C).

Now, I understand how this tone control works and that it blends the two passes together but when the pot is in its middle position it has no effect and yada yada yada...

But my question is...Why not use 39k and .01uF for both filters, or use 100k and .0039uF for both filters?  Why the combination?  It seems to me that using the same set of components for both filters would result in equal amounts of current through both filters.  Wouldn't we prefer this?  Does this have any effect on the sound?

[Skreddy]

They don't really have the same corner frequency, and there is a bit of effect in the middle position.  It's a mild mid scoop roughly in the 1k region.

I've played with a flat-response tone stack (recently!), and it's boring.    That's the bottom line.  This tone stack adds much of the "wall of fuzz" character to the Big Muff.  I use a mid HUMP modded version tone stack in one of my pedals, and it's really cool, too.  Sounds very different from a BMP.

The classic "triangle knob" Big Muff tone stack is 33k and .01uF (ceramic) on the lowpass side and .004uF (ceramic) and 33k on the highpass side.  That sonic signature adds to the creamy feel of the distortion.