Diode Blend Pot For Pharaoh?

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Diode Blend Pot For Pharaoh?

squirrels
I was wondering if anyone knew a way to replace the diode selector switch to a diode blend pot on the Pharaoh? I really just want to blend the silicon pair with no diodes, the asymmetrical germanium sounds weak and bland to my ears. This is mainly for aesthetic purposes but maybe it could add something interesting? I’m using a 500k pot in place of the hi/lol switch and it’s more useful. Any help or advice on different diodes to mix would be much appreciated.
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Re: Diode Blend Pot For Pharaoh?

squirrels
Would soldering the diode pair between one of the outer lugs of a 100k pot and the board and the middle lug to the board work? Similar to the blend pot on the Tonebnser MkIII it Fuzzsound?
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Re: Diode Blend Pot For Pharaoh?

Fuzz Prince Of Bel Air
This might be useful:
http://www.muzique.com/lab/sat2.htm
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Re: Diode Blend Pot For Pharaoh?

squirrels
Unless I’m not understanding it properly, I don’t know if it applies to Big Muff type circuits since the diodes are in the feedback loop and not to ground.

I just realized how badly typed my previous posts are. Sorry about that.
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Re: Diode Blend Pot For Pharaoh?

Fuzz Prince Of Bel Air
The best solution to your dilemma is simply to breadboard the circuit (or just the clipping stage) and discover what happens.

And I could be wrong, but the way those saturation controls in that link work is by using resistance to block how much signal is sent to the diodes, which is what I assume you're asking about...?

Anyway, I just shared the link in case it helped.
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Re: Diode Blend Pot For Pharaoh?

BetterOffShred
In reply to this post by squirrels
By adding a large resistance in series to the anti-parallel pair of diodes (I'd try it at the "in" or "out" point of the diode switch) you may be able to imitate a near open state up to a full closed state.  It's worth a try and is as simple as rigging a B1M or B2M pot as a variable resistor in series with those diodes.  

Let us know how it works

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Re: Diode Blend Pot For Pharaoh?

squirrels
Thanks for the suggestion. I tried putting the silicon pair and switch between lugs 2 and 3of a B1m pot  and it just cut the signal out when turned fully counter clockwise. I also wired it the same way I would do a cap blend using the little vero layout here: 

https://www.diystompboxes.com/smfforum/index.php?topic=94413.0 

I replaced the caps with two diode pairs and got nothing. I’ll just leave it alone. The switch works fine, it’s juTs more for aesthetics and I don’t have room in the enclosure for a rotary switch. 

I used that cap blend on a Colorsound Overdriver and it works fantastic. The BAT Black Forest layout squealed when I I built it so I gave this a shot instead. I think I’m going to try it out on my Colossus instead of the cap switch. 
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Re: Diode Blend Pot For Pharaoh?

Sphere80
This post was updated on .
Way Huge Pickle MK2 has two of these diode pots. One between LED and silicon, the other silicon and bypass.

This diode pot is a common feature on VFE pedals too with the center position sounding like the diodes are bypassed.  There's the Alpha Dog (Rat) on the main page, and the Fiery Red Big Muff, which you can find at Madbean.  There's also the Distortion 3, which was one of my first layouts here:
http://guitar-fx-layouts.42897.x6.nabble.com/VFE-Distortion-3-quot-cubed-quot-layout-td36720.html

Most of the time, I was good with a B100k pot, but some diode combos required more experimentation to avoid dead spots and make the transition smooth.  The VFE  pots use a center detent, but you'll hear when  the diodes sound bypassed.

 As far as the germanium pair, double up to raise the level.