I need help TODAY!!!

[bigben55]

I installed my new Gotoh bridgeplate and soldered up my new Rio Grande pickups(Muy Grande bridge and Dirty Harry neck) last night. Basically all I did was to unsolder the old pups and resolder the new ones in the exact same spots. I didn't do the copper shielding job. Everything works and sounds as would be expected BUT, the hum and noise is pretty bad. What could I have done wrong or neglected/omitted that would cause it? I'm thinking I didn't ground something correctly. The one thing that I keep thinking is that the Keystone bridge puickup that was in there had three wires, not two. It had a black, a white and a BLUE. The blue wire is just soldered(looks like from the mfg) to the backside of the bridge pickup between the middle two magnet indents and was run straight to the tone pot. The Muy Grande only had two wires, so I ran the HOT to the switch and the ground to the tone pot.

Was that blue wire a ground of some sore that I no longer have? How can I fix this?

I do plan on doing the shielding job today even though that means uninstalling and reinstalling everything. The hum is pretty bad.

HELP!

[max_twang]

First off, try reversing the leads on the input jack. I wired mine backwards once and had the same problem...Good luck!

[sjtalon]

KS pups:
The blue wire grounded the bridge base plate, and bridge and strings via the mounting screws. The Neck blue wire also grounds the neck cover.

If your new bridge pup has a metal base plate, the neutral wire would be ( is normally) connected to the base plate by a jumper, to ground everything there.

If you have a hum, and touch the strings and it subsides, that not only means the bridge plate is tied to ground, it also means the output jack is wired properly.

If the jack were backwards the noise would get WORSE when you leave go of the strings.

A continuity test with a multi meter would confirm your ground.

Base plate, control plate, jack cup should ALL have continuity to each other.

If your new bridge pup doesn't have a metal base plate, you will have to run a separate plate ground wire.

[bigben55]

Problem is the mug grande doesn't have a metal baseplate for me to solder a ground jumper to. Is there a work around? Maybe the bridge plate or something?

[sjtalon]

Some lift the plate up and crunch a wire under it. The easiest way is put a small ring terminal on a wire and put it on a bridge pup mount screw, between the plate and pup tubing.

Then run that wire to ground naturally.


I was editing my other post so you may have to re-read it but I see you know about the bridge base plate deal.

[bigben55]

Going to try that, run a wire from a bridge pup mounting screw to the tone pot. Do you think that will fix most of the hum?

[sjtalon]

Well it will help in that when you touch the strings, your body will act as a shield.

Some pups just buzz worse than others and being you had KS's you got spoiled

[Thighbanez]

Originally Posted by sjtalon

Well it will help in that when you touch the strings, your body will act as a shield.

Some pups just buzz worse than others and being you had KS's you got spoiled

Lol...

[garrett]

Originally Posted by sjtalon

The Neck blue wire also grounds the neck cover.

It grounds the shield, but not the cover. Bill's covers are plastic, just there for cosmetics.

Originally Posted by bigben55

Going to try that, run a wire from a bridge pup mounting screw to the tone pot. Do you think that will fix most of the hum?

It will reduce the buzz (but not completely since the guitar isn't fully shielded), but you will still have hum because it's a single coil.

[sjtalon]

Originally Posted by garrett

It grounds the shield, but not the cover. Bill's covers are plastic, just there for cosmetics.

grounds what shield ??

Respectfully my friend, I don't think Bill added a wire for looks, the PLASTIC cover is CHROME coated............which is conductive.

[bigben55]

I took it all apart, soldered a wire to a star washer, put it from the tone pot to a bridge pu mounting screw and reassembled. Problem solved! Thanks a lot guys. There's still hum but no worse than my g&l legacy. The Rio Grande's sound amazing! The Muy Grande is a little noisier than the Keystone. The Dirty Harry is considerably noisier, but its supposed to sound like a P90 and those are notoriously noisy. Full review to come.

[garrett]

Originally Posted by sjtalon

grounds what shield ??

Respectfully my friend, I don't think Bill added a wire for looks, the PLASTIC cover is CHROME coated............which is conductive.

You're right. Hard to respond with my foot in mouth. Don't multitask when you post and think before you type is all I can say.

I hadn't even considered that's how he shielded those. My 298TL is shielded, yet has no cover or baseplate. I'll blame it on belief it was magic. :-p

[sjtalon]

bigben good you got it cookin' !

Hey garrett, everytime I open my mouth I have to change feet !
Glad to hear you didn't take my comments in a bad way.

Happy pickin' everyone.