Arbiter Fuzz Face

Even the gnarliest effects collections are finite, and mine is no exception. While I still have some awesome pieces left in the tank for you, they are in various locations and states of repair. Instead of talking about a stone cold classic or future classic that I do own, it’s time to talk about some important pieces that I do not.

And firstly, I want to get one thing straight: The Fuzz Face is my favorite circuit. I’ve built hundreds of them for various folks and myself, I’ve built them with drawers full of crusty parts occupied by the essences of repairpersons past, and I’ve built all sorts of features into them and around them. I’ve agonized over the circuit’s shortcomings and its finickiness. I’ve tried every value and configuration of those 11 components and found some great value sets and plenty of stinkers. And after all that, I’m still learning new things almost every time I put pen to paper. It’s perfect, and I want to tell you all about it.

If you’ve ever cracked an electrical engineering textbook, there’s a good chance you’ve seen the Fuzz Face schematic in some form. It’s derived from a type of circuit called a shunt-series feedback amplifier. In fact, if you Google that term, there’s a good chance that a rudimentary Fuzz Face schematic will come up, minus a part or two. This was adapted by Ivor Arbiter from a different Sola Sound design with a change to biasing. Original units were built into the bases of microphone stands, giving them their characteristic hubcap-like shape.

Perusing the Internet for pedals will invariably lead you to reading all about the guts of these beasts, and the nuts and bolts that everyone is constantly geeking out are transistors. But not just “transistors” as a necessary piece of the puzzle, but rather tons of different varieties and part numbers. If you’re not aware, there are thousands of different transistor part numbers, with several of them regarded as legendary components. Of these heralded parts, the big one for our purposes is the NKT275, a germanium unit made by Newmarket Transistors Ltd, out of Suffolk in the UK.

Some die-hard tone snobs swear up and down that true Fuzz Faces and its copies can only contain NKT275s, and an even smaller percentage of players won’t accept anything less than period correct passive parts around them. Newmarket was one of several small germanium transistor companies in the UK around the mid ‘60s. Though some schematics of the oldest Fuzz Faces falsely reported that vintage AC128s were used, it didn’t take long for the Internet to debunk it, and the already-small number of these parts that existed in the wild suddenly vanished, and so finding them in 2021 is extremely difficult. It doesn’t help that not every germanium transistor, let alone the 275, is guaranteed to work well, and as they weren’t developed explicitly for guitar effects, there is no assurance that they will even sound good in the circuit. Requiring two meant ordering seven. And if you can find seven NKTs to begin with, there is a good chance they’ve already passed through the hands of someone looking for the same characteristics. Don't even get me started on the influx of counterfeit NKT devices.

One of Arbiter’s engineers, Denis Cornell, used to hate building and testing them because no two sounded the same—different parts have different gain values and “leakage,” after all—and they’re sensitive to room temperature on top of that. And so this extends to the concept of “good ones” and “bad ones.” If you’ve ever marveled at the price of some of these old units, this can have quite an effect on that value.

With all that said, the germanium Fuzz Face is quite a thing to behold and play. The right gentle calibration can turn a good sounding pedal into a great one, where it will exhibit some warm low-gain tone and some glancing sponginess when rolled back. Mike Piera of Analogman can tell if a transistor is good just by plugging it in and scratching the guitar strings. Now that’s feel.

Speaking of newer-school boutique manufacturers, let’s talk about the origins of the Fuzz Face renaissance. In 1984, Crest Audio, the new name for Dallas Music Industries (who themselves co-branded the original Fuzz Face after partnering with Arbiter in the ‘60s) reissued the Fuzz Face built by Dave Fox, now of Foxrox. But those used silicon transistors, an alternate supercharged version of the circuit. The first germanium boutique clone I can think of was developed by Cesar Diaz, called the Texas Square Face.

This unit was built to replace Stevie Ray Vaughan’s Fuzz Face units that Diaz claimed were in constant states of disrepair. Diaz was offering these as early as 2003 on his website, though his gear lineage is much more storied. But Diaz was using standard off-the-shelf germanium transistors by NTE, a brand sold at hobby shops and commercial electronics stores.

Germanium transistors haven’t been made in decades, and so finding them is increasingly difficult. Many pedal companies that offer a readily-available germanium device use transistors from Russia, where they were manufactured in gargantuan quantities well into the late ‘80s. Finding non-Russian devices for large commercial purposes is getting more and more difficult.

Even the most bespoke manufacturers are veering into Soviet territory, with careful adjustments to the surrounding passives to both pay homage to the past and break new ground in the future. And with a sterling catalog of players in the history books to match a broadening base of users, the Fuzz Face rules over all. Forever.