I have seen on various web sites that people will "line" the recess where the magnetic pickups go with some type of shielding material that supposedly reduces interference and/or unwanted noise from the pickups.
Is it necessary?
Does it depend on the pickups? I am guessing cheaper pup may be more susceptible to interference?
What type of material is it?
Thanks
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I've been playing this morning before going into work and I think I figured this out. I believe I'm mistakenly using the terms hum and feedback in a audio sense and not guitar sense.
Now that I changed my grounding scheme, what I'm actually experiencing here is not hum as such but a odd effect created by my reverb pedal when is dialed into particular settings and I just touch a string with my brass slide when not palm muting. Hard to explain but it's a weird twang snap. Kinda out of this world, "space age" sounding.
Pretty cool actually now that I know how to tame it.
try a bone slide
I just may have to give that a go. I wonder where I can get one? ;)
Back to this again,..
A few days back, I decided to go in and modify my existing bridge to lower the action a bit on the 3-stringer I built. It was pretty much "quiet" before but did notice that I could drop a very slight (and I mean slight) background hum that I was detecting at moderate and higher volumes. This would completely go away if I touched the pickup or the base of the jack cord. While I was at it, I figured that I would try grounding the strings by soldering a grounding wire to the bridge rod and ground it to the back of the volume pot.
This just made things worse and I'm not sure if it was lowering the strings so that they are closer to the pickup or the bridge/ string grounding I added. Now when I palm mute on or slightly behind the bridge it's dead silent. The fireworks now happen when I'm not physically grounding the strings with my body. In effect, my efforts to drop this very slight background hum that existed made it worse :)
I initially was going to solder to the jack ground lug but decided to solder to the back of the vol. pot where all my other grounding was located anyway. I'm thinking that this might has been a bad decision and actually have created a ground loop issue by doing this. No big deal opening it up again to re-locate the grounding wire to the jack ground lug but I lose a set of strings every time I open it up.
Anyone care to comment on whether or not they think that moving the ground wire from the back of the volume pot to the Jack ground is going to fix this or am I chasing the wrong thing?
You can get copper shielding tape pretty cheaply on ebay. You can also get slug tape from Lee Valley, which looks like the same thing.
Slug Repellent Tape
I suppose I'm going to have to give this a go. I've got a roll of Al. tape so hopefully using that will improve things. Isolating the pickup is going to be the hard part, though. It's not too difficult in a solidbody where the pup is sitting in it's own recess but a completely different thing in a CBG.
Can't you use the self adhesive copper tape, and just wrap the bottom part of the pickup with it?
I could do that I suppose but I would need to pull the screws that fasten it down in order to do so. I have it mounted to the thru neck inside the box and not the lid if that makes any sense.
I guess I'm still trying to understand what I'm trying to isolate the pickup from. I'm only working with a pickup, volume control and jack here and I haven't created a ground loop with my ground wiring that I can see. My pickup is grounded to the back of the volume pot as is the jack. The only addition to that is the bridge which is also now grounded to the back of the volume pot in the same fashion.
If I "enclose" the back of the pickup and also ground to vol. pot it would be just more of the same I would think. <head scratch>
The thing I'm trying to understand here is if this is a grounding problem, a pickup isolation problem or if they are one in the same.
Dan Sleep
The high end custom guitar builders use copper foil and stick that to the bottom of the pickguard. On a three single coil pickguard the copper foil will cover all three pickup routed holes(the foil will surround the routed holes by an inch or so on the edges) and be placed under the volume/tone pot and five way switch controls too. Then the copper foil will be cut out where it is covering the pickup route holes and the holes for the volume pots and five way switch. Grosh guitars would also place solder on a seam of the copper foil. All of the copper foil is soldered to ground.
I would do it on a single coil pickups, but on humbuckers I would not worry about it. You can use cheap aluminum foil out of the grocery store, but it is not as good of a conductor as copper. Just a cheap alternative and you would have to use and adhesive to stick it down. I have some old pickguards off of Kramer guitars and they used aluminum.
Sorry about responding to an old thread like this I was wondering if anyone have some photos of box cavity shielding like this?
I'm pretty close to installing my pickup and I'm pretty sure it's a single coil and not a humbucker. Only two leads coming out of it. The two being what I assume to be hot and a braided ground around it. The whole deal is in a single sleeve shield.
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