Neve knob Percolator....

[Dan0h]

I have wanted a Percolator in a 1590b for a while. I built one and it was so crammed that I had to try again. This one is awesome. Used a matched pair of 1n695 diodes, a 2n2907A for the pnp, and a bc109 for the npn. Brutal goodness! And crazy coincidence with the passing of Neve and these being my only Neve style knobs.

 

[Dan0h]

I know that these don't really get much above unity gain due to the germanium diodes at the end of the circuit, if you add a diode lift on a spdt switch you can get a massive increase in volume and taking away some compression gives a lot of dynamic range. Good looking build!

I’ve made three of these and all three have been way above unity volume. Very loud. Actually, just about every drive I’ve made has been very loud I can’t dime any of them. Not sure why.

 

[182julien44]

I know that these don't really get much above unity gain due to the germanium diodes at the end of the circuit, if you add a diode lift on a spdt switch you can get a massive increase in volume and taking away some compression gives a lot of dynamic range. Good looking build!

Do you have any schematics, or even better diagram or pictures on how doind this?

I was about to ask as I'm building one right now!

Thank you

 

[Dan0h]

what transistors did you use, are they both silicon? I used a 2n404 in Q1 and 2n3565 like the originals.

I made one to spec and one with different transistors. Pnp and npn. Both loud as hell.

 

[182julien44]

http://pedalparts.co.uk/docs/HarmonicPercolator-v3.pdf the schematic will show you how to wire it. you could do a dpdt on\off\on and have no diodes in center, si on one side and ge on the other.

Thank you very much I will do that to my percolators

 

[Dan0h]

http://pedalparts.co.uk/docs/HarmonicPercolator-v3.pdf the schematic will show you how to wire it. you could do a dpdt on\off\on and have no diodes in center, si on one side and ge on the other.

This rules. I’m going to try to perf board this lay out. Thanks.