EHX Knockout gain issues

a_magg · #1 06-30-2009, 05:27 PM

I've been using a Knockout for some time, and while its great for really shaking the windows and getting a solid sub sound, I'm having trouble getting used to the amount of gain that comes with using it. Even with my passive P bass, the pedal throws my amp into clipping with the Dry set at 2 o'clock and the Low below 11 o'clock.

I have not seen anything about this on TB, but does anyone have a suggestion for handling it? Perhaps a mod to control the amount of gain the pedal puts out? I really like the pedal, and at 70$ its worth trying to tweak it.

Thanks! - Andrew

judas jedermann · #2 06-30-2009, 11:52 PM

My setting usually are: low 10 `clock, dry 1 `clock, high all the way down. And it shakes the entire house.

thekage · #3 07-01-2009, 07:12 AM

I have to crank the lows all the way up and the take out the dry before it gets my amp to clipping. And I have active pups.

a_magg · #4 07-01-2009, 08:57 AM

Quote:

Originally Posted by judas jedermann

My setting usually are: low 10 `clock, dry 1 `clock, high all the way down. And it shakes the entire house.

Thanks for the settings suggestion. I'm someone who mods pedals stumbles in here, I guess I should've included that in the title.

My main reason is I'd like to set this to unity gain, so its not a drastic jump up in volume.

bongomania · #5 07-01-2009, 09:10 AM

If you really just want to reduce the overall output level, you could put an appropriate-sized resistor in series with the output. Otherwise I think you'd have to find the transistor that provides the gain, and replace it with a lower-gain transistor, and also modify the voltage feeding it.

a_magg · #6 07-01-2009, 09:13 AM

Quote:

Originally Posted by bongomania

If you really just want to reduce the overall output level, you could put an appropriate-sized resistor in series with the output. Otherwise I think you'd have to find the transistor that provides the gain, and replace it with a lower-gain transistor, and also modify the voltage feeding it.

Is there someplace that would help me out with that? In terms of what I'd be looking for, should I take a picture of the guts?

bongomania · #7 07-01-2009, 09:26 AM

There are only so many transistors in there. I would use an audio probe (see geofex or diystompboxes for details) to find out which one it is. Then I'd use the indicia on the existing transistor to identify its type and gain, and get a replacement of the same type and pinout but with lower gain. Measure the DC voltage into the existing xtr and write that down, as reference in case you need to adjust that voltage for the new xtr.

If it uses SMT (micro) components then you're hosed, unless you feel like learning how to work with SMT.

a_magg · #8 07-01-2009, 11:53 AM

Quote:

Originally Posted by bongomania

There are only so many transistors in there. I would use an audio probe (see geofex or diystompboxes for details) to find out which one it is. Then I'd use the indicia on the existing transistor to identify its type and gain, and get a replacement of the same type and pinout but with lower gain. Measure the DC voltage into the existing xtr and write that down, as reference in case you need to adjust that voltage for the new xtr.

If it uses SMT (micro) components then you're hosed, unless you feel like learning how to work with SMT.

Thats a lot of scary words haha, is there anyone per chance that would be willing to do this?