The Fuzz Detective

Discuss all non-Boss pedals here!
Post Reply
Luke Drifter
Posts: 189
Joined: Wed Jan 09, 2019 2:27 am
Location: West Australia

The Fuzz Detective

Post by Luke Drifter » Sun May 30, 2021 8:57 am

I found this to be really interesting
https://m.youtube.com/watch?v=VdJWv4emZdY

with some great detail in the comments, eg:

The MKii and Buzzaround are very different circuits.

The MKii is kind of like a booster in front of a fuzz face. There are a couple important things going on with it. The stock design requires careful selection of three transistors for the right gain and leakage to bias correctly -- even with a bias trimpot! The bias on the transistors is definitely part of the sound ... the second transistor is biased very low, almost completely saturated (even more saturated than a fuzz face), and the second transistor is biased closer to cutoff. The result is lots and lots of sustain, a highly asymmetrical waveform (unlike a fuzz face, which when biased at the halfway point "corrects" itself to symmetrical), with some interesting compression. The MKii had a lot of weird requirements that would have made it kind of tough for long-term production, probably the main reason they changed the design shortly after.

The MKiii also has a bass cut at the output (around the D string), and its fuzz pot provides less of a full range boost in general, so it's good at cutting through a mix. The biasing makes it sound kind of dark to me. (It would brighten up if biased more like a fuzz face.)

Structurally, the buzzaround and MKiii Tone Benders are very similar. A discrete pair of transistors form a darlington pair (they multiply their gain together ... and their noise, unfortunately) and slam a third transistor. They both have a couple "refinements" of, let's call them "post Fuzz Face" fuzzes.

The Buzzaround has:

1. Gain control is a standard volume control after the first and second transistors and before the third. It helps provides a stable bias for the transistor, though the third transistor does have to be germanium and selected for some leakage (for its positive bias) and gain characteristics. Also, this makes the bass content FIXED in the Buzzaround. That can be kind of important for ...
2. The tone control is a pan between a small (thin/trebly tone) and big (thick/bassy tone) output capacitors.
3. A balance control offers some interesting bias adjustments as well as a kind of crude volume control. You can actually get a very wide range of sounds. I think the original unit was particularly well-suited to being switched on all the time and hitting the front end of an amp that was already about to break up and really using the guitar volume for your total level control. You can make adjustments to the three controls to suit the amp but flipping it on for a solo could mean compromising getting the best sound for your gear.
4. NO output volume control on the original unit. Many people add it.
5. Comparatively low output impedance for a fuzz.

Tonebender MKIII has
1. Gain control is a SERIES RESISTOR going into the third transistor (think similar ot the Full Tone 69's smooth control). This means it can't "bottom out" like the Buzzaround. So it's less versatile in that regard.
2. Tone control is a now-bog-standard treble cut. Not my favorite control for a fuzz ... that cuts all those upper harmonics that you wanted the fuzz to create to sound like fuzz! But it can be better for getting more of a high-gain overdrive type sound out of the pedal sometimes, and it's not like it doesn't still sound fuzzy. I just think the Buzzaround's is cooler.
3. The bias is set with a fixed resistor where the Buzzaround's "balance" control is, essentially maxed out.
4. Output volume control makes it a little better for flipping on and off in the same song.

Both the Buzzaround and MKIII sound very "hard" to me. Like, hit a note and bam it's there. The feel is very different from the MKii in my opinion.

It's hard to talk someone out of getting any fuzz unless they're looking at something almost identical, like two "different" fuzz faces
Jerem, Jeremy on BAF and SBZ

Post Reply