Keeley Java Boost

[ckeibler85]

I got the java boost working.  However the 100kB pot used as a tone control doesnt do much but dampen the tone when its near fully CCW. Can anyone recommend a different pot value or taper to make it more useable? IIRC i remember reading something about 100k not being the value pot used in the original, though i may be remembering incorrectly

Also i have resistors from smallbear that are correct value to bias the oc44 transistor i got from him. How woyld i replace the trimpots. It looks like one of them has all 3 legs in use as a potentuomter rather than a variable resistor.

Thanks for any help yall.

[Ciaran Haslett]

There's only 2 pins being used in each trimmer on the layout from here.  Top right and middle on the 100K and top left and middle on the 10K.  Set them to the position at which the circuit sounds best, remove them and measure their resistance between said pins.  Then replace those pins with a fixed resistor.

Are you sure everything is correct around your tone pot connections?  Some reading suggests that it's not a very useful control on this circuit so I wouldn't be sure here.  Verify everything is connected as it should and then play with the 100n to ground.

[ckeibler85]

Hey man- Revisited this guy.  Tryin to get it there.  maybe I could substitute a value for the 100n cap to let it perform a little better.  All the play is at the counter clockwise portion of the pot, and it basically just dulls it down super quick in about the last 5% of the rotation if you're turning the knob counter CW.  So given all this I should probably try something like a 22n cap in place of the 100n cap, right? Or maybe try a reverse log pot?

Any suggestions would be greatly appreciated!!!

[kirshman]

Can you post pics of your build?  I've built no less that 10 of these for myself and friends, and the tone control should have an obvious effect.