whats shielding?( a newbie asks )

[Groverismybass]

can someone explain what that is and how to do it because my pick-ups have alot of buzzing ad humming, and i think thats what its supposed to fix

[SomewhatHarmles]

Shielding is essentially a thin metallic film that's usually placed between your pickups and the inside of your electronics cavity. It "shields" against feedback magnetic waves from the pickup.

You can buy specialized foil from StewMac to do it, or simply use aluminum foil with some 3M spray adhesive. However, it'll take some work.

I focus on acoustic guitars myself, but I'm sure that some of the people at MIMF can help you. You can also check out Kathy Matsushita's webpage on building a fender-strat style guitar for a simple thing on shielding. http://home.comcast.net/~kathymatsus...es/strat3.html

[mambo4]

Originally Posted by SomewhatHarmles

Shielding is essentially a thin metallic film that's usually placed between your pickups and the inside of your electronics cavity. It "shields" against feedback magnetic waves from the pickup.

Close but not quite correct: Shielding (good shielding) insulates the entire cavity of an electric bass, pickups, wiring, underside of the pick guard and all (not just the pickups.)

Shielding protects your pick ups and wiring form external Electromagnetic frequencies, like radio signals and AC power hum/buzz. An unshielded single coil bass can be a good radio receiver

Also, besides the foil there is also magnetic shielding paint, which you can use to coat the cavity.

[kraigo]

Originally Posted by SomewhatHarmles

You can buy specialized foil from StewMac to do it, or simply use aluminum foil with some 3M spray adhesive. However, it'll take some work.

You can go to a stained glass shop and get copper foil sheets. It solders just fine and the adhesive seems to conduct just fine so you don't have to solder each piece of foil to its neighbor.

KO

[debassr]

Sometimes, it's not the bass that's doing it either. There are a couple of noisy outlets in my house that I have to avoid plugging my amp into otherwise I get a lot of hum.

Also, sometimes the grounding cable that goes from the pots to the bridge doesn't make good enough contact with the bridge and therefore causes noise when you're not touching the strings. You can check that as well.

If all that fails, *then* consider shielding your pups and control cavity.

[Groverismybass]

hmmm

[Bassamatic]

Important - The foil pieces must all be connected to ground, and to each other. This is why it is important to use the copper foil from Stew-Mac. The adhesive is conductive. If you use spray adhesive, the pieces may or may not be touching, so no shielding. You then solder a small wire from the foil in each cavity to the main cavity.

The underside of the pickguard must also be covered with the foil and connected to ground.

Done properly, this can make a HUGE difference. The first time I did it, I thought that the bass was not working, it was so quiet.