About diodes

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About diodes

Argider
Hi guys,

So I've only built an EHX LPB-1 on vero ten years ago. But really digging the sound of the Pharaoh Supreme fuzz pedal and would like to build it. I have a couple of questions on diodes in this use context though:

The pedal I meantioned earlier has a daughter vero board consisting of the different diode choises to make the clipping effect, as I've understood, so:
1. Can I use LED and MOSFETs, or any two diodes, as diodes in parallel as a clipping setting or is it a nono that will just sound crappy?
2. Do all germanium diodes or low voltage diodes work for as clipping diode in this type of context? Or is there some voltage minimum or maximum I need to look at when choosing diodes?
3. Can any three-legged MOSFET be used as a clipping diode by joinin the two of the legs as one leg?

Thanks soldering gang!
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Re: About diodes

PMowdes

Hey

1.  you can use LEDs, and different colours will yeild different results.  Diodes in series, yup. MOSFETs,  yes i think so.
2. Ge diodes for sure, they give a different quality.  Warmer, more rounded, but lower volume.  Si diodes give a harsher, more brittle clipping.   Check out the Spaceman Gemini fuzz, it is a blendable GE / Si fuzz you should be able to hear the difference between the two.  

https://www.youtube.com/watch?v=AEic-WyxEno

3.  You'll have to ask someone else.

In general it's about forward voltage and the knee.  You can get an idea from this eevblog video  

https://www.youtube.com/watch?v=O0ifJ4oVdG4&t=822s