StompBoXed - The Guitar Pedal Builders Repository: February 2018

Fuzz Face Mod - 1k Pot

You want to put together a fuzzface type circuit from items in your junk box and you don’t have the 1k pot for the fuzz control.

What can you do?

A simple mod is to replace the fuzz control with a fixed 1k resistor – this sets the dc bias properly. Then connect the 22uF to the emitter of Q2 and use a 5k or 10k pot as a variable resistor to control the amount of distortion, as shown to the left.

The new larger value pot should be a reverse audio taper for best results but a linear will do if that’s all you have in the junk bin.

It is not the classic circuit but this can get you going on short notice when you lack the proper parts.

Jack's original post is here on his blog: http://www.muzique.com/news/fuzz-face-mod/

Also see: Joe Gagan's EASY FACE schematic :

Fender Blender / Vero PCB Layout Schematic

An oldie, but a goodie!

One of the company's most iconic effects, the Fender Blender Fuzz Pedal has been an effects staple in genres like indie and shoegaze since its introduction in the 1970s. Bringing together fuzz and octave capability with controls for tone, volume, sustain, and blend, the Blender's famously been seen on the boards of Kevin Gates of My Bloody Valentine and Billy Corgan of Smashing Pumpkins.

Boob Tube v 1.5 * Valvecaster Variant *

Based on JuanSolo's 12V Boob Tube which is a Valvecaster variant, but here with a 33 - 40V supply via a charge pump. Make sure you choose appropriate 50v capacitors for the voltage.

Here's the charge pump, if you supply it with 12V you should get close to 40v from the 33v output point.

NOTES: If you want to supply the charge pump with 9V to avoid using a 12V adapter, you could use a 12V regulator off the 17V rail to provide the 12V required for the heater, or maybe even a voltage divider from the 25V rail. In this instance you would only get around 33V for the plates though.

Yes this is verified, and it sounds great!

The Colorsund One Knob Fuzz

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Valvecaster - Tube Overdrive / Boost Pedal

While I know we've posted this previously, I found this layout to be one of the more useful ones. Look into our archives / previous posts for more Valvecaster layouts. Power source I was getting better results with 12v 1A, see Garth's 24v version below. -K

Another idea is to incorporate a boost of your own choice (i prefer the alembic stratoblaster) and hook that up before C1 . This gives the pedal an extra boost to the circuit so it distorts more. I would use separate pots for this, not a dual pot.

WIRING DIAGRAM w/ LED & True Bypass Footswitch

GARTH's VALVECASTER w/ MODS @ 24V

Dallas Rangemaster - Point to Point


The Traditional Dallas Rangemaster

Rangemaster w/ Modifications

Lovepedal Superlead Layout / PCB

Snow Day Overdrive - Jon Patton Designed

SolaSound Tonebender MK III

The Mark III was a smoother and less aggressive follow up to the famous Mk II Professional. SolaSound built it for several other companies–Vox, RotoSound, Park, etc. There are plenty of layouts for this classic fuzz out there already (there's already 2 on this blog), but I drew this up for a 2-in-1 box I'm putting together (this into a Catalinbread RAH) and thought I'd share. So here's a modern layout for the ToneBender Mk III.

Originals used PNP germanium transistors, so the perf side reflects positive ground layout, but the PCB side shows negative ground if you want to use NPN transistors.

EarthQuaker Devices Acapulco Gold

Tonally, it's based on a cranked Sunn Model T amp and uses 2x 386 chips. It cleans up nicely with the guitar's volume, so a good mod would be adding a pot before the input. John K did this and used a reverse log 1M pot.

1964 VOX Tone

Here's another (nearly) new one from me. It's a tricked out super mod of the old Electro Harmonix LPB-1 circuit that produces some lovely singing overdrive tones reminiscent of an old VOX from their 1960's heyday. I took the Lovepedal Englishman (A supposed Vox AC30 / AC15 emulator) as a base and went from there - Firstly I wanted a little more gain, hence the 4k7 collector resistor. Along with more gain I wanted more emphasis and clipping on the higher mids to replicate that treble laden Vox overdrive hence the 82nF bypass cap and the 47k/22nF mids filter at the end of the circuit. These changes make the circuit sound livelier and give it more character. The use of the *super* low forward voltage SB340 diode in combo with the BAT46 diode produces harmonically rick asymmetrical clipping, the levels of which can be controlled using the "Headroom" control. The headroom control also allows a nice rich low end to be retained while allowing the top end to be clipped, as you roll back the clipping a nice tube like "note attack sag" effect becomes prominent - it's quite pleasing and cool to play with. The use of the 2N3565 transistor is due to some tests carried out a while ago where it was found that the 2N3565 sounded best in these sort of applications, you can replace it with a 2N5088 or BC108 or, in fact, any decent gain NPN transistor.