First off, I'm
not claiming this to be a "scientific breakthrough" and anyone with a basic knowledge of electrics would be able to figure this fix out for themselves.
No, the people that this thread is aimed at are the people like me, who are a bit intimidated by mystical forces that they can't see
(a.k.a. electric current
) and would like to rid themselves of that irritating hum that occurs when taking your hands off the strings on old Fender basses.
So, what's my suggestion!? Well, it's incredibly simple and only involves a 2" long strand of bare wire, a screwdriver and a fully shielded pickguard (or a metal template under the plastic guard, like on a vintage P)
. The result is that the screw on the top of the split pickup
and the pickup cover itself (if you use it) will be "earthed", so that
whenever you rest your thumb on either the pickup or the chrome cover, there will be no hum (just as it disappears when you touch the strings).
I will add a disclaimer here: I don't know what impact this modification would have in the event of an electrical short circuit, where live current is passed through the input jack, but I suspect that it would only make things worse
. Experts feel free to chime in
.
"
What use is this mod?", you ask. Well, it's very useful if you're recording into a PC or laptop, where the monitor causes a lot of hum, or in a room with fluorescent lights etc.
Here's what I did ....
1. Remove the pickguard and metal shield.
2. Remove the pickup screws and plastic covers.
3. Take the 2" (bared) strip of light gauge wire, wrap it around the top (thickest part) of the shaft of the pickup screw, then twist it to form a loop through which the screw can pass. Leave the remaining wire untwisted and bent up at 90 degrees from the loop.
4. Holding the piece of bared wire by the untwisted ends, slide it down against the side of the pickup cavity and then lower the pickup (with plastic cover ON) into the cavity, until the loop is lined up with the hole on the underside of the plastic pickup cover.
5. Thread the screw through the plastic cover and through the loop in the wire. This can be a little fiddly to do, but much easier if you have enough loose wire on your pickups to be able to pull them right out of the body to thread the wire loop onto the screw, outside of the pickup cavity.
6. Once you've got the pickup loosely screwed down, with the loose ends of the bared wire poking upward, out of the pickup cavity, you then need to poke the loose ends into the screw hole where the upper screw holds the chrome pickup cover in place. Don't worry if you don't use your bass with the covers installed, it won't matter
.
7. Now all you have to do, is re-assemble the bass
. Start by putting the metal shield plate back on. If you don't have one of these, (or metal foil stuck to the entire back of your pickguard),
this mod isn't going to work on your bass .
Now, the metal plate is making contact with the bared wire, as well as the screw that it's attached to AND to the output jack (which is earthed to the metal plate
).
8. Next, install the plastic pickguard and the control knobs, etc. Now you're down -
go crack open a beer 
!
9.
Put the beer back in the fridge and come back - you forgot to put the strings on
.
Anyway, see those strands of wire in the pic above, poked into the hole? They're your friends if you prefer to play with the chrome covers on
...
Pretty obviously, now that you've effectively linked the pickup screw and the chrome cover screw into the earth part of the circuit, any time that you touch them, the effect is the same as when you touch the bridge or the strings. The real advantage of this mod is that the bass will stay totally silent, even if you take your hands off the strings (as we all have to at some point),
provided that you're a player who rests his/her thumb on either the pickup or the metal cover when playing.
I've made this mod to both of my P Basses now and am very happy with the results, so I wanted to share this tip with you
. The best part is, there's no need to make any solder connections or any permanent modifications to your (valuable) instrument.
I hope that my explanation was clear enough to follow and that it's not just a case of "stating the obvious"
!?
Thanks for reading!
