We have had a major renaissance in fuzz pedals in the past decade or so. New and old makers and alike have brought out dead-on renditions of mid-’60s germanium fuzzes, late-’60s silicone fuzzes, modern fuzzes with knobs to control every parameter of the circuit, and more. Rather than being the extreme distortion effect that the uninitiated might presume them to be, good fuzz pedals can sound very organic when used right, and can interact beautifully with a cranked tube amp to produce a broad palette of overdrive tones, from mild Rolling Stonescrunch to full-on sting. Certainly you can elicit the “bees in a tin can” sound from ill-conceived fuzz use, but legendary players from Jimi Hendrix and Eric Clapton to Jeff Beck and Keith Richards have also used fuzz pedals to produce some of the richest, most expressive guitar tones in history.

One thing that a lot of players don’t consider amid this sea of fuzz options, however, is how to power the things. On contemporary units with AC/DC converter inputs, many guitarists just hook up their wall-wart with daisy chain and forget about it… but in the old days, players in the know understood that, in addition to the fuzz interacting with the amp, it also interacted very directly with the battery installed in it. Many guitarists still believe that a lot of fuzzes, and the vintage style units in particular, are happier with batteries than with power converters, and that they might actually sound better with an old-style 9V carbon-zinc battery installed, too. For some of the thinking behind this, let’s turn to Zachary Vex of Z.Vex, one of the more creative “mad scientists” among the new breed of pedal designers.

“There are two things you need to know about carbon-zinc batteries,” says Vex, adding, “and some people have huge beliefs that carbon-zinc batteries sound better for fuzzes.”

The first thing: “Carbon-zinc batteries have got a very high start voltage. The start voltage in a carbon-zinc battery can be 10.5 volts. I’ve seen them at 10.6 or 10.7 start voltage, even. You don’t see that so much anymore – Rockets used to make them that high; I can’t seem to get Rockets any more – but I can get ones that are 10.2 or 10.3. At that higher voltage you seem to get a little more ‘zip’ out of a fuzz.” That extra “zip,” as you might guess, puts a little more bite and edge on the tone of a fuzz that is affected in this way.

Modern-style alkaline batteries, on the other hand, tend to start at around 9.2V or 9.3V at the most, a whole volt lower than the average carbon-zinc battery, and although they deplete more gradually and more steadily, they also don’t give you that crucial “zip” at the top of their life span, if you’re looking for a fuzz tone with more cutting power to it.

Dave HunterThe second thing regards the output resistance of different battery types: “Batteries have an output resistance just like a circuit does,” says Vex. “For carbon-zinc the output resistance is much higher to start with [high being a good thing], and it gets terrible toward the end of its life. It becomes so saggy that if you try to pull any power out of it, it just goes ‘ppphhhh…’” And while that sounds like a bad thing, Vex says it can yield another soft, squishy fuzz tone that some players really dig under certain circumstances.

“Alkalines, even toward the end of their lives, never have such a high resistance, so you never experience them going through the same sort of phases of that output resistance thing, and you also don’t see a big spread of voltages over the lifetime of the battery. Alkalines are much more stable, so they’re kind of nominal. You see a lot more changes in fuzz pedals over the lifetime of a carbon-zinc battery: you’ll hear pretty oscillation things you’ve never heard before, you’ll see a roundness to the waves [on an oscilloscope] that you’ll never have with an alkaline battery.”

What does all this mean for the workaday fuzz-loving guitarist? Well, get your hands on a selection of different carbon-zinc batteries, and see how they perform in your pedal. You can obtain an affordable volt meter (a.k.a. multi-meter) at Radio Shack, set it to the 20V setting in the DCV range, and measure both new and old batteries to learn what DC voltage they are actually putting out, then find which levels produce the tones you prefer. Even when you nail that perfect voltage, however, maintaining it can be frustrating.

As Vex, a former studio engineer, relates: “When I was recording in the studio sometimes we’d get a fuzz sound that was just incredible, and then it was late at night, maybe two o’clock in the morning, and we’d have to go home. In order to preserve the sound, so we could continue recording the next day, I would always unplug the fuzz or maybe even pop the battery out to protect it. Then we’d come in and hook it up, and for the first couple of minutes it would be a little brighter, because [the battery] comes back to life. There’s a change in the chemistry when you take the load off, and for a little while they’re a higher voltage. It is kind of creepy.”