Tonestyler types, and Gretschy mud switches work fine - they're basically like switching in a tone knob rolled all the way back, but the ability to choose the cap gives you more or less lowpass effect....
The varitone is more of a bandpass (the inductor cuts the lows and the cap cuts the highs), so more in cocked wah territory, but passive and lower Q, so more subtle. For my taste, I prefer the non-inductor variety, but that's consistent with my overall preference for lowpass over bandpass. I've gotten good use of a varitone though, so like most of these things its about hooking shit up, twiddlin' and listenin' - you might like the way a varitone sounds better.
Setting a varitone up with a blend knob increases chances of happiness - the blend controls how much of the effected freqs are shunted to ground - it's not a Q control, but it can help if you want a little less honk.
It's intersting that Gibson came up with the Varitone, given the general middiness of their pickups already. I've always thought a varitone might work better with a strat....
You can throw a varitone circuit into a pedal box and it works just fine, I assume a tonestyler type cap selector switch would work just as well....
Being passive, these circuits are less prone to making your precious Mullard'd tropical fish fuzzface go all wonky....
As expected, you'll also get different kinds've howls from oscillatin' devices - could be good, could be worserer - ymmv.
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