Build Your Own Clone Message Board

I used the mods for the "Boutique Fuzz" at ggg, very easy.
You need to add two linear pots and they fit nicely on the side of the box.
This gives you added control over the sound of the fuzz.



I actually didn't use the byoc board but had to build point-to-point because I added the transistor switch mod. The toggle and the extra pots together took too much space.
What a huge difference between the silicon and germanium! Especially between an active and passive pick-up.
The only problem I had with mine was the fuzz knob killed the sound until you went past a 1/4 turn. Same if it was the 1k or 2k pot (I stayed with 2k). I had to send it off before I could tweek it right.

Very cool, thanks for the clear diagram. I'm going to revisit the Fuzz Face after a few other builds, and will definately try this out. Thanks much!

-editted-

Was thinking about modifying the basic Fuzz Face I have already assembled with a couple of the mods I have seen posted on the BYOC message board. Intended to reuse all the kit parts and source the everything else. So, I am wondering about the 2.2uf and 0.1uf capacitors in this diagram. Do you usually discard once-soldered capacitors and resistors for new? What is the practice when making up these off-board changes that chain parts together where the PCB provide space for only one component? Can you do things like splicing in wire segments after trimming the leads down short instead of twisting very long leads into eyelets?

Yes, of course. Anything you can do to create desired continuity between components is fair game.

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*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Here it is with a byoc board and sourced parts. Tight fit in the small box but it does fit. I used a tantalum for the 2.2uf cap, it actually sounded better to me. The transistors are from Small Bear, they sound great. I liked both sets that came with the kit too.
10,000 shades of fuzz.

Which transistor did you choose from SBE for this Fuller mod? Your photo is very clear, I can almost make out the ids. Guessing they are a AC128 or NKT275 germanium pair.

It's silicon 2n3440 http://www.smallbearelec.com/Detail.bok?no=491
I didn't see any NPN germaniums at small bear.

Those are PNP. The board is designed for NPN transistors with negative ground so that there is no ac power issues. That's why the kit comes with AC127 germanium transistors...they are the NPN compliment to the AC128.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

I asked about that before.
The original Fuzzface was positive ground, the ggg negative ground schematic switches the polarity of those two caps (2.2uf & .22uf) the byoc board keeps them in the original position. Keith said it didn't matter which way they went, I tried both ways and in all possible combinations and it worked every time. So I guess he's right, it doesn't seem to matter.

Hey Scott - where did you get the Smaller Black Fluted Knobs? I've been looking to get a large supply of those and have not been able to find them.

Thanks, Greg

At Antique Electronics http://www.tubesandmore.com/ Somewhere on there, I have a hard time finding things on their site.
They have two sizes, the larger one is just a little bigger than the byoc stuff. It's the same as what Analogman uses. The small ones are perfect for tone controls, I use one for the middle knob on my tube screamers.

Thanks Scott!!!

Yea, I've found a few in some old surplus supplies that I've had for a while and they work great for the middle knob on any three knob pedal (Delays, Screamers, etc.). They also work great on four knob pedals. Just the right size. Thanks again for the info.

By the way, your fuzz with the contour and bias looks great.

so, the bias knob is meant to dail out the bass(Excessive in stock form?) and the conture dails IN midrange? that sounds pretty good. That 50k pot, there's nothing special about it right? just a regular 50k linear?


any idea why the fuzz knob didn't work until it was turned up 1/4 way?

what do you mean you had to send it back?

how would you say the bias knob mod would compare to dano's switch mod? http://beavisaudio.com/Projects/FuzzLab ... zzmods.htm

I have a slightly more than cursory knowledge of electronics, but I don't know how a cap switch with different values compares to a cap in series with a resistor.

Thakyou very much for the mod pics and instructions btw!

The first one I built had issues with the fuzz knob, the second didn't. I'm guessing now that the problem was with the pot itself. I didn't actually try to replace the 2k pot but just put a resistor across it to cut it in half. So when I said it was the same with a 2k or 1k pot I was really using the same pot, dumb mistake.

I send all my pedals off to a musician who actually gigs for a living so I rushed that first one off, the second I took my time with.
I except to see that first one again some day, it had an additional ge to si switch that's not going to hold up.

So the difference between dano's switch and the bias knob is great. Those silicon transistors that come with the kit have much more gain and grit than the germaniums, switching them in was like punching in an overdrive. The bias knobs just tweeked the bass, midrange and gain to taste.

sorry.. I meant to ask how does the fulltone "bias" mod, compare to having a bass cup cap selector (on the 2.2uf) like dano did

assuming the that Bias is meant for cutting bass

That I couldn't say. I'm sure the input cap switch does a much better job cutting the bass. I'm guessing here, but maybe the bias controls how much distortion is on the bass.

If you're going to put in an input cap selector consider the Seymour Duncan Tweak Fuzz aka Afrofuzz http://board.buildyourownclone.com/viewtopic.php?t=862

I've done the 69 mod and the bias knob works great. But the contour knob just seems to be another volume knob. I've checked my wiring already. Is it just me?

hey bro go up a few threads to the required reading and check out the tech of fuzz in it is the fuller mods and explains the input pot and how it works. if i understand it right it is kinda a volume thing but has a purpose related to input impedance.

The Contour adds more output and gain from Q2. It allows you to dial in many of the mods people have done over the years. Most notably Roger Meyer supposedly, amongst other things, replaced the 470 ohm resistor with a 1k resistor in Jimi Hendrix's Fuzz Face.

Using the Contour knob allows you to go from just below the "Stock" FF settings through the "Hendrix" FF mods and all points in between.

I have done the "69" mods and think they are highly worth while.

Also, I never use an internal trim pot. I use a B50k external pot wired in to the trimpots spot on the PCB. That way you can adjust the Bias based on how hot your pickups are. This too is a must do as far as I'm concerned.

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I... have become... uncomfortably numb...

A few questions (sorry if they're stupid):

With the '69 mod the bias pot is connected in series with the 2.2uf electrolytic cap - why is this & why not just use an external 10k pot connected to the terminals for the internal trimpot?

What is the funtion of the 1k resistor in series with the 01.uf film cap?

On the picture of the PCB showing the '69 mods there are 33k & 470 ohm resistors on the top right (where the contour pot is connected) but on my PCB there is a third resistor, 4.7k; what is this doing?

Thanks for your help. Matt

...ah...after a lot more searching this forum I've discovered that what Fulltone call a 'bias' control is actually a variable bass cut, whereas the bias trimpot actually biases the transistors.

I also read that the 1k resistor in series with the 01.uf film cap has little effect & can be ignored (true??)

So the only remaining quesrtion is what is the 4.7k resistor on the new PCBs for?

It would be really useful if someone were to gather all the information on the '69 mod together in one place, partly for people like me who understand little unless it's spelt out for them, and partly because, now the Fulltone '69 is discontinued, more people will want to mod the UF kit & will ask these questions all over again...

Matt