DIY Roger Mayer Axis Fuzz (drawn by Justin Philpott) Can the highs be tamed?

[Burstbucker]

Many years ago, I built a fuzzbox following this schematic by Justin Philpott:

http://experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noisemakers/Roger%20Mayer%20Axis%20Fuzz.gif

I got it to work but never really bonded with it, so it sat in my dresser for the last ten years or so.  Tonight I decided to plug into a bunch of my old builds and I was actually surprised that this Axis Fuzz sounded way better than I remembered.

But it is super bright, way too trebly IMO.

Looking at that schematic that I followed, how would a person pull out some of the insane high end?   A capacitor between the output of the Volume control to ground perhaps?   I thought that I would consult with you guys since I'm just a hack following a schematic, so I could use input from people who know a whole lot more about this stuff than me.

[thermionix]

Weird, I just pulled one of these off my breadboard.  The cap to ground at the input is supposed to be 470pF not 47pF.  Should tame a bit of high end, can't say just how noticeable it would be.

Some versions also include a resistor and cap to ground at Q1C/Q2B.  Most online schematics show 220r>1n, though there is some debate that it should be 220k>1n.

[thermionix]

Couple more issues with the schematic you posted.  The 2.2uF cap is backwards (important!), and the two film caps depicted as "1" are supposed to be .1 (less important).

[Burstbucker]

Thanks guys!

I will have to tinker with this thing again.  So the cap from input to ground should be 10 times bigger?   Yeah I will have to try that.

And the 2.2 uF is indeed backwards, dang!   I don't know how that might affect the sound but I could possibly pop it's cork?

I think that there might be a diamond in the rough if I can get the bugs out of it.

Thanks again!   And any other comments would be appreciated as well.

[amptramp]

It looks like you have the tip of the input jack going to the battery and the ring going to the input.  Should this be reversed?

[thermionix]

^ Yep another error in that schemo.  I doubt Burst hooked his up that way though.

[Burstbucker]

 You're correct.  I did not wire up the input jack as shown on this schematic.

The pedal is operational but I would definitely like to dial down those super high end frequencies.

[zombiwoof]

The schematic that I saw years ago also showed a .002uf treble bypass cap across the volume pot to keep highs as you turn down the volume, like you put on a guitar, but I guess that would not be something you would want.
Al

[lcv]

Hi
The Axis fuzz features  an hi-fi, wide-band circuitry.
Distortion kicks in full of 2nd-4th-8th etc. harmonics and breakups.
On a similar circuit, Band of Gypsy FF, Dunlop put  caps all over the places trying to tame hights.

I had some success on an original Axis fuzz I own, soldering a cap (100p to 470p) from q1 emitter to q2 collector.
On my unit, the RF network on q1 collector was not populated. I'd suggest to omit it as it creates some additional crackling.
Regards
Lcv