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What do you think is the most essential element of a fuzz pedal?
Mayer: There isn’t one element. I mean, obviously, the overall sound. But that’s not an element, that’s a result of the element. There are many different ways to create the sound, and so many interactive things in the pedal. You can’t really say there’s one thing.
So it’s how they all interact with each other?
Absolutely! In the old days, the thing with the germanium transistors was the huge spread of each transistor. You couldn’t take a hundred out of a box and use the same components for each one.
Because they were inconsistent?
The gains would be all over the place, I guess.
Oh, all over the place. The leakage is all over the place. Are you familiar with the way transistors are made? Basically, the transistors are going to use a silicon or germanium wafer, and it goes through a bunch of processes—chemical etching, doping, and so forth. And then they’re put into an oven. Now, they’re gonna make quite a few transistors on a wafer, depending upon their size. And after these transistors are made, they’re all kind of diced up, almost like slicing a pizza into small squares.
Now, out of one die shape they might get, say in the case of the silicon transistor, 20 or 30 numbers out of it. But you’ve got all these variables—the temperature will be inconsistent across the die, the impurities of the doping, and all that. So they test each transistor and categorize it for low noise, high voltage, current gain, and so on. That’s how you get a whole series of numbers that are all the same. In the early days, the control process wasn’t as perfect as it is today. So consequently, there was quite a bit of a spread in the manufacturing. Especially with germanium, it was not quite as tightly controlled as silicon. It’s nothing to have a transistor selected for low noise, and then have the gain vary anywhere from 100 [hFE] up to 800 [hFE].
This was something, I guess, Arbiter didn’t know about.
Well, it’s not that they didn’t know. If you’re talking about the Fuzz Face, I’d say it certainly isn’t a device that’s the best example of a fuzz box, you know? Even though Jimi [Hendrix] made them very successful, the actual design is a complete disaster when it comes to temperature stability and everything else.
That’s why there were so few of them that actually sounded good.
That’s right. We make a version today, but we take a thousand transistors and select them out, and then we group them into pairs, and then we have a little preset on the card, just to tweak it to make it work properly.
You were probably the first to propose the idea that all the components needed to work together in this particular circuit for it to sound good.
Well, Jimi would buy half a dozen of these pedals, find one that sounded great, and then we’d mark it, right? One day it would work and another day it wouldn’t work so well in a different environment. Jimi would say, "What’s going on?" and I’d say, "Well, it’s got to be temperature, Jimi. That’s the only thing that’s changing." So that’s what got me to look inside the box. We got a good sounding one at a certain temperature, but as the temperature changed you could see the biasing completely shift. I started analyzing them a bit more carefully to find the combinations that work well. You might buy 20 pedals to find a really good one, but then it wasn’t stable at all temperatures. If you took it out of the trunk of a freezing car in the winter and brought it into the club, it wouldn’t sound too clever until it warmed up a bit.
I’ve heard stories of people putting a heat- er next to it.
Yeah, as I’ve said, the early ones were basically crap. Then they went on to the silicon ones, which had a bit more gain and high end, but they were terribly prone to pick up radio and start oscillating and were bloody unstable. We used to get around this in the studio by putting different buffers in front of the pedal. A Fuzz Face does not particularly like looking at the coil of a guitar where the output impedance is rising continuously, or it may squeal when it looks at a wah-wah pedal. It could be best described as a minimum parts circuit, for sure. It wouldn’t be something you’d deliberately go home and design, you know?
So there we have it, straight from the man himself. It’s good to remember that, thanks to the pioneering efforts of Roger Mayer, many boutique pedal builders today are familiar with fine-tuning component values to optimize a fuzz circuit.
See you next month. Until then, keep on stompin’!
(a.k.a. Analog Tom) is the owner and proprietor of For Musicians Only (formusiciansonly.com) and author of Analog Man’s Guide to Vintage Effects. Questions or comments about this article can be sent to: firstname.lastname@example.org.
(analogman.com) is one of the largest boutique effects manufacturers and retailers in the business, and it was established by "Analog" Mike Piera in 1993. Mike can be reached at AnalogMike@aol.com.