RG's SSRP - Mu amp and J113 !

[MartyMart]

http://www.geofex.com/
Scroll down to the mu-amp ssrp article.

I like the sound of these circuits, with its noiseless biasing and a couple of additions, this
makes a great Boost/ medium drive pedal, here's the additions :

I used in/out caps of 27n ( odd value, but choose perhaps 22n )
Attached a 4k7 pot, with wiper to a 33uf to ground off lower Q's source, pot's lug 1 also to ground
Added a reverse protection 1N4001 and a 100uf filter cap from 9v to ground
from pure clean to medium OD is available ..... lovely !

Jfets :
MPF102 was quite nice and I found that a J201 was a little "dark" sounding, then I tried a J113
which I had bought a while ago and never tried out ..... NICE
It has a bit more gain that an MPF102 and has a nice clear tone to it, I'm surprized that they
dont come up more often, its the same pinout and has a sweet sound 

There you go !
Thanks RG for another "good read" and great little circuit !

Marty.

[Johan]

yes, J113 are nice, and since you're in europe too, may I also suggest 2SK117...dont know what it is...just sweet somehow...
and yes, the Mu-amp in its different carnation is a great little circuit and we all owe a big thank's to Jack Orman for digging it up out of the archives...

johan