Strange Buzzing After Treble Bleed Mod.

[dan2002]

Ok, I just got a new P-94R to stick into the bridge of my Epi. Les Paul Special (I know, I know). Well, I noticed the treble was bleeding off, so I do the treble bleed mod with the 0.001uf cap on the hot and middle lugs of the volume pot. Now, after doing the mod, I get a loud buzz when I have the P-94 selected. When I flip over to my bridge 500T no buzz, hum, no strange noises. I noticed when I move the guitar in certain directions it stops, but im positive its not interference. Its not grounding either, because when I touch the pickup cover, the buzzing gets amplified. I went in the electronics cavity and I pushed the 2 wires from the P-94 that dont get soldered onto anything, down off to the side, and the buzzing stopped alittle. Confusing. Sorry for the long post, but its really bugging me.

Dan

[crafty]

I pushed the 2 wires from the P-94 that dont get soldered onto anything.

What are you talking about?

Green and bare to ground.

White hot, black to ground. Reverse if out of phase with bridge pickup (sounds thin when in-between).

Edited March 13, 2006 by crafty

[dan2002]

Ok, I grounded it, I was mistaken, when I installed the p/u I thought you twisted them together and that was that. But the strange thing is that it worked perfect before the mod. After I grounded it, the buzzing went down alot, but it still is there, and not on my 500T.

[crafty]

The 500T is much more capable of dealing with buzz and such than the P-94 because it is, well, a humbucker. I would recommend that you fully shield the pickup and control cavity, run all the wires as short as possible, and use the star grounding method, with all grounds leading to a common point before grounding it all to the bridge.

Does the buzzing go away when you move the guitar about like before, or when you switch to the in-between setting on the switch?

[dan2002]

The 500T is much more capable of dealing with buzz and such than the P-94 because it is, well, a humbucker. I would recommend that you fully shield the pickup and control cavity, run all the wires as short as possible, and use the star grounding method, with all grounds leading to a common point before grounding it all to the bridge.

Does the buzzing go away when you move the guitar about like before, or when you switch to the in-between setting on the switch?

Im doing the star grounding method, and yeah it still varies when I move around, and in the middle some of the buzzing is still there.

[crafty]

Well, it sounds like it just might not work with the treble bleed mod. It might actually have a side effect of boosting the frequencies that cause the buzz that the P-94 is susceptible to. You might shoot off an email to Gibson and see if they have any other ideas. Sorry.

[lovekraft]

We're just talkin' about a cap that's connected to two adjacent lugs on the same pot - disconnect one end of the cap and see if the buzz disappears. If it doesn't immediately disappear (and I seriously doubt that it will), you've got another problem. Also, keep in mind that the treble bleed mod (if wired correctly) will have no effect whatsoever with the volume wide open, since the cap will be shorted out completely, so if the offending buzz is present at full volume, it's not coming from the treble bleed circuit. Are you sure you didn't accidentally "mod" some other part of the wiring while you were in there (I do it all the time )? Your description sounds suspiciously like a ground loop, so maybe you've shorted a ground wire somewhere.