# Vintage Style Fuzz Face (Battery Box Mini Content)



## Big Monk (Apr 18, 2022)

“Jesus H. Roosevelt Christ Monk, are we still yammering on about Fuzz Faces? 🙄”

😁

If you can sit through my rambling, maybe I’ll have a point in the end…😂

I’ve gone deep into the Fuzz Face recently. “The Fuzz” was a real technical and practical deep dive for me and I’ve really come to love the Fuzz Face topology.

I always thought I was strictly a Mk II guy, but goofing around with the Fuzz Face and figuring out all the levers, what they do, how they interact, etc. has proven to me that it’s circuit topology, and it’s inherent simplicity, belies a depth and complexity of rich fuzz tone.

Recently I came up with a temporary configuration for a new pedalboard that incorporated all the pedals that survived this last and final purge of my circuits I had left. I wanted to test placement, wire routing, etc. and now that I have the final configuration plotted out, I’m looking to future proof by adding 3 more spots and configuring my available power ports for the 16 taps I need.

Currently I have a TrueTone CS-7 handling all my digital stuff, my E-Lady, Aion Ares and my Overdriver (on the 18 vDC tap) and my 7 tap Otraki supply handling dirt, wah, and my Boss CS-2.

The plan is to expand the Otraki with a 3 plug daisy chain and use a LM2596 regulator module and 1590A to make the 15 vDC tap into a regulated 3-14 vDC tap or run it straight through for a filtered 15 vDC tap for extra flexibility and to run the Monk Vibe.

Whew! I’m rambling here.

To the point! Get to the point!

I want to have a dedicated battery box in the board to run Vintage style fuzz builds in the space immediately after my wah. I’ll be using the battery box mini from PedalPCB when it comes es back in stock.

So the first Vintage style build will be a Fuzz Face. It’s my desire to make a true vintage style Arbiter Silicon Fuzz Face with just a few concessions to noise and modernity. I have the board designed and the graphics done, which I’ll post here tomorrow, but here are the basic specs and design choices:

- No LED
- Power from battery through the battery box (so it’ll have a DC jack to interface)
- No power filtering
- Single sided board with bottom ground plan
- Pad rings hidden in top layer to give the vintage look
- Follow the basic layout of the vintage Arbiter board, but with the following small changes:

  • PCB Mounted pots (requires some           slight tweaks from the vintage board layout)
  • 22 nF RF cap from input to ground
  • 100-180 pF Feedback bypass cap
  • Extra ground pads for shielded wire

- I’m going to try and match the basic aesthetic of the vintage components with high quality modern equivalents including:

  • Vishay Electrolytics (similar in style and look to the old Philips caps)
  • CDE 150 Series tubular films caps
  • Vishay-Dale brown Mil-Spec 1/2W metal films

I’ll post up some pics tomorrow of the graphics and board. Big thanks to @SYLV9ST9R for helping me with the original artwork I had laid out for another SiliFace project that got scrapped. I used his QC of my work and the old file to prepare the current one.


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## Big Monk (Apr 19, 2022)

As promised (to whom I don't know!). Enclosure will be Tayda Dark Grey (same as for the Monk Vibe):





Board keeps the basic topology of the old Vintage Fuzz Face:


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## Feral Feline (Apr 19, 2022)

Looking forward to hearing and seeing this one.


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## Big Monk (Apr 19, 2022)

Feral Feline said:


> Looking forward to hearing and seeing this one.



I ordered the boards this morning and I’ve got a Tayda order in the works and I’m going to order 2 enclosures for this as well. 

Just need to wait for the Battery Box Mini to be back in stock!


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## fig (Apr 19, 2022)

I can send you mine if it would expedite your project.


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## Big Monk (Apr 19, 2022)

fig said:


> I can send you mine if it would expedite your project.



Fig’s General Store, open for business!

Thank you Tim. I can wait though. It’s not an emergency.


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## Feral Feline (Apr 20, 2022)

"I need two battery boxes, STAT..."


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## Big Monk (May 2, 2022)

Components and boards are in!:


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## andare (May 2, 2022)

Big Monk said:


> • 22 nF RF cap from input to ground


Does that mean your FF won't pick up radio stations? Say it ain't so!


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## Big Monk (May 2, 2022)

andare said:


> Does that mean your FF won't pick up radio stations? Say it ain't so!



Yeah! That and the feedback resistor bypass cap kill almost all noise with only a marginal darkening of the tone. I dropped the input and emitter cap to compensate so it should sound exactly the same, frequency wise.

There is also the 10 ohm in series with the emitter cap that kills that classic end of Fuzz knob travel noise.


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## andare (May 2, 2022)

Big Monk said:


> the feedback resistor bypass cap


Is that cap parallel to (across) the 100K resistor?



Big Monk said:


> I dropped the input and emitter cap


Lower values for less bass, right?


Big Monk said:


> the 10 ohm in series with the emitter cap that kills that classic end of Fuzz knob travel noise.


Not familiar with that noise. My Fuzz knob is always backed up a bit from 100% because otherwise I'll never get a completely clean tone with the guitar volume rolled back.


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## Big Monk (May 2, 2022)

andare said:


> Is that cap parallel to (across) the 100K resistor?



Yup. In this case 82k but that's the same resistor.



andare said:


> Lower values for less bass, right?



Yup. Adding the capacitors to eliminate extraneous noise, hiss, RF, etc. dampen the higher frequencies slightly so making changes to the input cap and emitter cap help to maintain the core tone.



andare said:


> Not familiar with that noise. My Fuzz knob is always backed up a bit from 100% because otherwise I'll never get a completely clean tone with the guitar volume rolled back.



Traditionally in the Fuzz Face circuit, you get a perceptible amount of extra hiss and sometimes RF with the knob up all the way. The 10 ohm acts like a hardwired limiter.

Also, lowering the feedback resistor a touch and focusing on Q1 bias voltage seems to have a pretty big effect on the "clean" tone of the Fuzz Face.


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## Big Monk (May 2, 2022)

With transistors:





Need to get this breadboarded to find out which value of Rc2a I’m going to use. 

I ended up just buying 4.7k-6.8k so I could find the right voltage. Also, I realized I don’t have any 1kC or 500kA 16mm PCB mount pots left so those will have to go on the Tayda order.


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## Big Monk (May 2, 2022)

Silicon version is not on the breadboard after the long “The Fuzz” residency:





With 6.2k for Rc2a, Q2 biases up to around 5.45 vDC. 

Sound tests to follow. Not sure if I’ll stick with 6.2k just yet. 

I pulled 2 Telefunken (TFK) BC108B at 300 hFE. 

While looking through my transistors I saw I still have a near perfect set of Germanium 2N169 General Electric transistors so I’ll of course do the Ge version vintage style as well.


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## Big Monk (May 3, 2022)

Sounds test. As always, pardon the playing, I was just trying to show the roll off/roll up characteristics;


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