# Foxx Tone Machine



## Chuck D. Bones (Apr 1, 2020)

Seems like everyone offers boards for this vintage box of nasty.  Truly an unruly fuzz, it's best for single notes, even with the Octave turned off.  Aion added two mods to this board set: a 3rd position on the OCTAVE switch that bypasses the Octave diodes completely and a 3-way MIDRANGE switch that offers different capacitors values in the Tone section.  The OCTAVE switch's full bypass mode allows the 2nd stage to overdrive the 3rd stage even harder when the SUSTAIN control is cranked, providing a thicker tone.  The MIDRANGE switch provide a deep scoop, a moderate scoop and almost no scoop.  The only thing I did different was to use a 2N1308 germanium transistor as the 3rd stage.  Not sure it makes an audible difference, but... Mojo.   I used 2N5089s for the other three transistors, per the BOM.  Octave diodes (upper left) are BAT46 and clipping diodes (bottom) are D2E.  Note that the board is laid out for two different transistor pinouts: E-B-C and E-C-B. The generous parts spacing permitted me to use some of my fatter film caps. This is my first build with a Tayda copper hammer tone box.   There was a so much paint in the holes that I had to chase the threads with a 6-32 tap.  Labeling will be a challenge due to the textured finish.  I originally put clear chickenhead knobs on.  They looked great but didn't quite clear each other.  The Aion mods could easily be applied to the PedalPCB Fuzzy Fox.  No matter whose board you build, I highly recommend reading Aion's Build Docs.  Although this pedal makes plenty of gain and volume (knob setting shown is for unity), it is possible to get considerably more volume by reducing the emitter resistor on the last stage.  This circuit runs the bias fairly cold on all four transistors, probably because the original units were battery powered, making low current consumption desirable. The biases could be fiddled to obtain more gain, volume and/or headroom.  I exercised some restraint and kept the stock bias settings.


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## Nostradoomus (Apr 1, 2020)

Nice! I just got my fuzzy fox board in the mail, retiring my old vero build!


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## Mourguitars (Apr 1, 2020)

Looks great Chuck...the hammer tone looks great as well...i would leave it label less


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## jjjimi84 (Apr 1, 2020)

Looks great! Aions build docs are top shelf, I have read everyone of them because I have zero life.

Even before covid


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## Gordo (Apr 1, 2020)

You're on a roll Chuck.  Very nice.  I usually have a few boards kicking around waiting to get built but lately have finished boards waiting to go into non-existent enclosures.  I should pick up a few projects...looks like we're in this for the long haul...


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## music6000 (Apr 1, 2020)

Was wondering when the Hammer Tone would appear.
How many was it?
Nice Build!


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## Chuck D. Bones (Apr 2, 2020)

Thanks guys, I had a good time putting it together.  No extra holes either!


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## Mir9 (Apr 2, 2020)

This was going to be my next build. I have a Daneelctro clone , which sounds good, but I still want one I can mod.  Glad I can use Schottky diode for the octave, and this 3rd octave mode with more sustain.    What would be the first things to try if I want even MORE fuzz, as I always do?


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## HamishR (Apr 2, 2020)

Ha!  You used almost exactly the same knobs as I did when I first used one of those boxes.  I built a Red Rooster into one and used those knobs but in silver.


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## music6000 (Apr 2, 2020)

Why does this remind me of MC Hammer!?


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## Chuck D. Bones (Apr 2, 2020)

Mir9 said:


> This was going to be my next build. I have a Daneelctro clone , which sounds good, but I still want one I can mod.  Glad I can use Schottky diode for the octave, and this 3rd octave mode with more sustain.    What would be the first things to try if I want even MORE fuzz, as I always do?



Referring to Fuzzy Fox ref designators...

Try increasing the gain of the 3rd stage.  Make R14 330R.

Make C9 larger for a fatter sound.  Try 15nF.

Try increasing the gain of the 1st stage.  Make R2 100R and C13 220pF.  Before you try this, put a booster in front of the Tone Machine and see if overdriving the 1st stage sounds good to you.


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## Nostradoomus (Apr 2, 2020)

I’m just gonna do it, driving the first stage always sounds good!


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## Mourguitars (Apr 2, 2020)

Chuck D. Bones said:


> Thanks guys, I had a good time putting it together.  No extra holes either!




lol


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## Nostradoomus (Apr 7, 2020)

Chuck D. Bones said:


> Referring to Fuzzy Fox ref designators...
> 
> Try increasing the gain of the 3rd stage.  Make R14 330R.
> 
> ...



Built mine up. R14 and R2 both 330r (because I had them out lol). C13 220p, C9 15n...this thing rips. Makes me want to jam along to Earthless all day. Used GAY63 diodes matched at .206Vf for D1 and 4 and used my trusty 1n5817 for hard clipping. It’s spicy!

Changed volume to A50k as well, B50K is silly.


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## Chuck D. Bones (Apr 8, 2020)

Color me silly, I followed the Build Docs and used B50K for volume in mine.  Unity is around 9:00.  I may end up changing mine to A50K.
I ran my SHO in front of the FTM, it was extremely nasty.


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## Hexjibber (Apr 8, 2020)

Great build, this thread is gold! This circuit was one of the first fuzzes I built and I’ve always loved it, really intrigued to revisit it with the mods outlined above, they sound great!


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## Nostradoomus (Apr 8, 2020)

Do eeeeet!


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