Removing the sweep cap in a wah

[liddokun]

I was modding my vox wah last night, and I couldn't decide between having either a .01uf or .022uf sweep cap, so I ended up putting both on a dpdt.  I forgot the check the switch type though, and I realized afterwards that it's an on-off-on switch.  Well, in the off position, obviously there is not sweep cap connected.  What I noticed is that I end up getting a nice little treble boost that I actually really like. 

So, being a curious person, I ask, why does this happen?

[tcobretti]

I have a feeling that you are essentially cutting the second transistor from the circuit, so the first transistor boosts the signal thru the cap on its emitter and out of the circuit.   Does it actually boost the signal, or does it just cut the lows?

[liddokun]

It seems like a tiny boost, but it may just be my ears. 

[asfastasdark]

According to RG in his article "Technology of Wahs" on Geofex, you can do a mod with a switch that selects from a number of different capacitors. He says the different values change the sweep range, and somewhere else in the article it talks about a higher value moving more towards the bass, and a lower value moving more towards treble. So by putting a really small value capacitor, "0 uF" (if you see what I'm saying), what might be happening is that less (or maybe even no) treble is being filtered to ground, and maybe that's why? I don't know... It's possible.

[liddokun]

That seems logical.  However, when I have the switch in off postion, it's not as if there's a jumper with 0uf going across, it's as if there is no connection at all there.  So, I tried it out, by removing Q2, and I get the same effect.  I guess the first transistor really is just boosting the signal through the cap. Silly me.  Oh well, now I have 3 settings on my wah, phat, twang, and treble boost.