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The Fuzz Rite is a fuzz box whose tone would be called typical 60ies – raw and fuzzy. It is similar in construction to other contestants of the time in so far that the available semiconductor devices at the time were low gain compared to contemporary devices and circuit designers would try to wring the most performance out of those transistors with appropriate circuitry. It thus has an input stage similar to the then ubiquitous fuzz face and a relatively high output impedance, meaning  one may encounter severe problems trying to interconnect the device with other devices just like with a fuzz face.

People have made extensions to the Fuzz Rite, mainly Gus with his Rite Fuzz and a designer called RnFR with his Green Bomb. Also, there is a plethora of fuzzes that use a similar topology, as shown on the fuzz comparison chart on Aron Nelson´s page.

One of the measures to exploit gain is the grounded emitter. Since in a common transistor voltage amplifier stage the gain is mainly set by the ratio of the collector resistor versus the emitter resistor, a grounded emitter will yield the most gain within margins. This also will limit the available headroom, which is why the Fuzz Rite can sound very gated at some settings. From a viewpoint of fidelity, a bad thing, from a musicians viewpoint, maybe a good thing. As usual, the beauty lies in the ear of the listener.

Also, this may not work equal with all transistors, so a first improvement is to include small value emitter resistors. Also, the original had the low band pretty much restricted (a sound which must have been favored in the sixties), so the Gus Rite and Green Bomb use much bigger capacitors for extended bass.

Of course, this changes the tone away from the original. A designer and forum member called RnFR has added a control that lets you sweep everything from stock grounded emitter (for the first stage at least) to a phase cancellation tone similar to the original on the other side in his Green Bomb circuit. This trick is not far from genius.


Also, the „fuzz“ control in a Fuzz Rite architecture differs significantly from other fuzz box topologies in that it does not change the amount of signal that hits a subsequent stage (like in a classical tube amp). Most contemporary fuzz boxes have an „amp-style“ gain control that sets the amount of signal going into the device and an output volume control to compensate the volume increase, while the overall gain is usually kept unity. The guitar´s volume and the fuzz control are somehow interacting (one of those fuzz boxes is the Boss Tone).

The Fuzz Rite architecture does of course provide some fuzz adjustment, but it rather blends the signals coming from two amplification stages, the one in front and one that is daisy-chained to the first (out of phase), and with a volume increase towards second stage settings. This architecture leads to a wide range of tonal possibilities from very gated over octave effects to fully nasty distortion, which other fuzz boxes cannot produce. Very versatile, if one likes the basic tone.

But it stems from the very same topology, that the guitar´s volume control is the only way of changing the amount of signal that hits the first gain stage. It is therefore of prime importance, to have a good working volume control, one with more than an on-off-action. The (input) buffer does away with that problem, without changing the overall tone.  The theory behind that has been explained at length in my Poker Face article.

So, yes, the Fuzz Rite is a good design. But it can be augmented.

Block diagram  (click for details). I did initially not consider my augmentations a "circuit" worth drawing, but for the sake of clarity and due to popular demand I have added a block diagram. The internals are documented elsewhere at length anyway.

I buffered the thing, as I have layed it out in my Poker Face article.
What was called the „fuller mod“ on a fuzz face, namely a series resistance that creates some sort of current drive on the input, also works on the given topology. One may indeed want to make this variable, but I decided to make it fixed. Too many knobs. I chose a 5k resistor in series, which does not drop the voltage significantly and simulates the impedance of a single coil drive. The tone remains unchanged by this measure, as A/B comparison shows.

Also, a 250k Pot on the output is not exactly low-impedance, so the output got buffered as well. The output buffer will eliminate tone-sucking due to long cables and drive problems possibly caused by subsequent devices and does not contribute significantly to battery current consumption.

The "on"-LED by the way is comprised of the usual ultra high efficiency LED out of a defunct head-lamp in combination with a 15k series resistor for ultra-low current demands one could only have dreamt of just a few years ago. A lens bezel helps to disperse the somewhat pointed beam.