Thanks again to everyone who chimed in on the “What your favorite mod?” discussion. I got tons of great ideas from your comments.
Like this one, which I’ve been meaning to explore for ages: the Fender TBX tone control circuit, which appears in several Custom Shop instruments, notably the Clapton signature Strats. Like the G&L PTB circuit I’m so apeshit about, it’s a 2-band passive tone control — but one that sounds very different.
The PTB is a two-knob circuit that lets you siphon off highs, lows, or both. I’m agog at how well it works with humbuckers — you can get so many cool sounds by rolling off lows on the way to a fuzz, as heard here.
But TBX (it stand for “treble bass expander”) is a one-knob circuit, tbough that single knob rotates two stacked pots. The control has a center detente. Set here, it’s like a regular tone control, wide-open. Turn it counter-clockwise and highs vanish, per usual. (You could “tune” the roll-off frequency with various capacitors, though I went with the stock .022uF.) But when you rotate clockwise, the absence of lows makes glassy highs erupt.
Technically, it’s not a boost, but it sure feels like one. Dirk Wacker, my now-colleague at Premier Guitar, dissects the circuit far more capably than I can here. (And he goes way beyond in this subsequent article on TBX mods. Man, I have some catching up to do!) He makes a good case for replacing the stock resistor with another value, but I went with the original 82K to establish a point of reference. I’ll try his mod when I restring, and I’ll update you here.)
BTW, you need the Fender TBX kit for this project — it uses highly customized pots to work its magic, and a standard stacked pot won’t do. But it’s cheap: You can find the TBX kit, with the pot, hardware, and passive components, online for about $15.
I put it into the mongrel strat I’ve been using as my digital synth/looping guitar. I’d been using a Stellartone Tone Styler, a cool Vari-Tone variant that switches between multiple capacitors. I dig it, but it’s the old model which clicks, rather than fades, from setting to setting, and it requires a powerful twist of the wrist to go from maximum to minumum, which I do every time I grab an EBow. Since I hadn’t gotten around to replacing it with the smooth-action version, I figured I’d try the TBX.
And I’m glad I did. It’s a super-easy install, at least to the extent that any job that requires removing both strings and pickguard can be easy.And here’s how it sounds:
I’m going to keep this one around for awhile. You’re hearing it through an analog rig, obviously, but I want to find out whether that extra shot of highs does anything meaningful when playing digitally. I’d also like to experiment with different cap and resistor values.
And now I can’t help wondering whether this would sound cool with humbuckers. Anyone have any experience with that?
