# Twin face



## K Pedals (Dec 18, 2019)

This thing sounds really good!.!.!
Best sounding one so far!!!
Got ASY36S on one side and BC108 on the other...


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## Barry (Dec 18, 2019)

Looks great!


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## K Pedals (Dec 18, 2019)

Barry said:


> Looks great!


Thanks man!¡


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## JetFixxxer (Dec 18, 2019)

One of my favorite fuzz....


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## cooder (Dec 18, 2019)

Tidy! Very nice build and makes me curious to put that on my list as well.... sigh...


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## Chuck D. Bones (Dec 20, 2019)

Another fine build!


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## K Pedals (Dec 20, 2019)

Chuck D. Bones said:


> Another fine build!


Thanks man!!!


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## music6000 (Dec 20, 2019)

Chuck D. Bones said:


> Another fine build!


Cool Build !

Hi Chuck, Where could you put a Tone Control or Internal Tone Trimmer on this.


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## Chuck D. Bones (Dec 20, 2019)

It all depends on what you want to do with the sound.  You can reduce the Bass going into the distortion stage, or boost / cut Treble on the output.  You can try a couple of things outside the enclosure to see if either of these gets you the desired tone.  You can build these on perf, Vero, breadboard or air-circuit.  
*Bass cut:* put an A100K pot in series with the input, wired for minimum resistance at full CCW. Put a 10nF cap in parallel with the pot. Turning the pot CW reduces Bass going in. You can try other cap values, but 10nF is a good starting point.
*Treble boost / cut:* build a BMP tone stack and connect it between the output and the next pedal or amp. This experiment will work best with the TwinFace VOLUME maxed out. If this does what you want, it can be inserted inside the box, ahead of the VOLUME pot. If the Bass is too weak, increase C2 & C4 to 100nF.
If you really want to go crazy, build a TMB tone stack and insert it ahead of the VOLUME pot.
Any tone control added to the output will reduce the max volume.  To get the volume back up, increase R3 & R7.  Try 1K.  If you need even more volume, go higher.  You will have to readjust the internal bias trimmers if you change R3 or R7.

There are FF-type pedals on this site that already have tone controls built-in.  The Dung Beetle for instance.


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## Fever2112 (Jan 3, 2020)

Would a 22uF e.Cap be a problem or is the 20uF required?


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## Chuck D. Bones (Jan 3, 2020)

Given that electrolytic caps usually have 20% tolerance (or more), 20uF and 22uF are interchangeable.


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## Fever2112 (Jan 4, 2020)

Chuck D. Bones said:


> Given that electrolytic caps usually have 20% tolerance (or more), 20uF and 22uF are interchangeable.


Thanks, that is pretty much what I thought as well.


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## Fever2112 (Jan 17, 2021)

which BC108?   108B or 108C?


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## K Pedals (Jan 17, 2021)

I’ve used all of them 
I like C


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## Coda (Jan 17, 2021)

My first build was a Twin Face, way back in April...I found it hard to play over the summer. The GE transistors I used did not appreciate the heat. Nowadays the GE side wins hands down. The Si side is just a little too...different. Mine prefers single coils. It was a great first build.


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## spi (Jan 18, 2021)

That's the first time I've seen resistors to join the pcb to the switch.  Did you use 0K resistors?


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## spi (Jan 18, 2021)

Coda said:


> My first build was a Twin Face, way back in April...I found it hard to play over the summer. The GE transistors I used did not appreciate the heat. Nowadays the GE side wins hands down. The Si side is just a little too...different. Mine prefers single coils. It was a great first build.


I built a Twin Face not too long ago.  My Ge side and Si side are pretty similar.  But I like Ge for the old school mojo.


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## Fever2112 (Jan 18, 2021)

K Pedals said:


> I’ve used all of them
> I like C


in this build?


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## K Pedals (Jan 18, 2021)

Yeah
I’ve made a lot of these ...
I’m making one right now

I try to make sure the hfe is larger for Q2 than for Q1...
So I’ll do around 80hfe for Q1 and 120hfe for Q2...


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## K Pedals (Oct 16, 2021)

spi said:


> That's the first time I've seen resistors to join the pcb to the switch.  Did you use 0K resistors?


Yep just 0 ohm


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