# Benson preamp clipping diodes



## Boba7 (Aug 11, 2020)

Hey guys

So the Chase Bliss preamp gave me the idea of adding switchable clipping diodes to the Benson preamp, and Im wondering where to put them. 
I don’t have a Benson preamp right now, gotta build one again soon, so Im just thinkin out loud!

My first idea would be to put the switch after C6 (22n), with a resistor (1k, 10k?) between C6 and the diodes. 
Another idea would be to put it after the treble control, parallel to C9. Chase Bliss mentions that the diodes in their preamp are after the treble pot in the signal path, dont know if its technically true though

Then I imagine the silicon clipping used in the Chase Bliss preamp is just a pair of 1n4148 (think tube screamer, they say) but the asymetrical germanium clipping Im not sure (think Klon Centaur, they say, but the Klon uses symmetrical germanium clipping right?) Maybe just 3 germanium diodes?

What do you guys think? Interesting?


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## Boba7 (Aug 14, 2020)

Haha I guess Im the only one interested then! Ill let you when I try it


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## Flying (Aug 14, 2020)

I'm guessing putting in some hard clipping diodes would not be that hard to do, but it sounds like the silicon diode is soft clipping from the description _'symmetrical silicon setting (think tube squeezer flavor)'_ could that be done with some sort of big muff clipping diode arrangement? But now my total lack of knowlwge is showing.

For me it's the mids slider that is exciting.


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## Boba7 (Aug 14, 2020)

Yeah the mids sliders are exciting! You could kinda do it with a JHS Haunting mids on a switch I guess (and even have 3 Q positions instead of 2)

You may be right about the soft clipping thing, I hadn’t even thought about it, looking at the Benson circuit my mind went directly to diodes to ground. Hmmm


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## Flying (Aug 14, 2020)

If the germanium diodes are 'Klon' like then they would be to ground, but it is curious that they are asymmetric! Is 'tone pony' a comon nickname for a Klon? or are they alluding to something else?

If the 'TS' style is soft clipping then I really do't know it would be implemented.

I've not looked at the Haunting Mids, but will do now, thanks.


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