Adding a treble boost to a broad-spectrum boost

[suncrush]

I built a nice little broad-spectrum transistor boost pedal that I'm quite happy with, and want to box up.  But, before I do, I got to thinking about trying to kill two birds with one stone.  I have an old DOD Vibrothang pedal, which notoriously rolls off some of the high end of your range, and makes your tone much darker.  I thought about making the boost switchable between broad-spectrum and treble boosting.  I know of a few ways one could do that, in principle, but I was wondering if anyone had suggestions from experience trying to do something similar.

[Kipper4]

Let's see what you built and then suggestions might be more forthcoming please.

[suncrush]

Yeah, good call.  I built this, without modification:



Works great for what I want it to (solos on a Strat into an Orange Micro Terror), except that I'd like to be able to turn on some more treble when using the Vibrothang.

[Kipper4]

if you have a breadboard why not. make a High pass filter on the output between A and C4.
I say breadboard it then you can test and tweek it before you add it in to the circuit.

eg
A> spst switch (on off) then a cap (small value probably nanofarads) then a pot wired as a variable resistance to ground)

set the pot to where you want it. switch the high pass filter in with the switch. or put the high pass filter on a footswitch if needed.

[suncrush]

So, a little messing around, and I found that simply switching in a 10 nF cap in series with the existing output cap works like a charm.  Is there any reason not to do that?

[Kipper4]

Nope.
It might pop when switched but then so might my idea.
If it sounds right it is......