Do I even need to shield my Jazz bass?

#24
I must have gotten very lucky. My American standard jazz bass is still stock (and unsheided to this day. I've had it over 3 years.

Never has this bass had the 60 cycle hum.

Stock pickups.

I can solo either pickup completely hum free.

I have had other jazz (mainly MIMs) that had awful humming going on.

Feeling lucky.
 
#25
tlc1976 said:
I've shielded basses with aluminum foil and glue stick. My uncle also shielded his fiddle this way. I realize it's not the true copper foil but it's dirt cheap and readily available. Night and day difference compared to no shielding.
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gelinas666 said:
I've used Aluminum Foil Tape that you use on Duct work.. Works great! :thumbsup:
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Ditto here on the duct foil tape. I didn't have any copper tape (or conductive paint) handy so I went with what I did have. Between that and running a wire from cavity to cavity to common the whole thing it worked a charm. Not the professional way to do it I know but for the beater bass I put it in... hey... it works.
 
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#26
It helps sometimes to ground the electronics to the cavity shielding. If you're using that foil duct tape everyone has recommended it's really easy to do. Just shield the cavities, and then solder one end of a wire to the back of one of the pots or to a ground lug, and use the foil tape to tape the other end to the cavity shielding. Some basses now come with this already done via a wire screwed into the shielded wood (the ones with the black shielding paint).
 
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#27
Faraday cages ... the more 'conductive' the material , the better it will work/shield ...

Silver , Copper , Gold , Aluminum , Zinc , Nickel , Brass , Bronze , etc > ...

a cheap noise gate pedal would probably be the easiest for a little buzz ...
 
#28
campbems said:
You are seeing alot of builders and bass company's using a special paint that shields the cavities. Does this seem to work as good as the shield tape?
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In theory, no. The black paint that is commonly used it low-grade and it doesn't offer the same resistance. This is like the junk Stew Mac sells for a high price. The gray paint you see, MG Chemicals Supershield, is on par with tape. In practice, pretty much any material will perform as well for our applications. I have had basses be just as silent regardless of my choice of aluminum or copper tape or paint.

mikeyjm2 said:
Ditto here on the duct foil tape. I didn't have any copper tape (or conductive paint) handy so I went with what I did have. Between that and running a wire from cavity to cavity to common the whole thing it worked a charm. Not the professional way to do it I know but for the beater bass I put it in... hey... it works.
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Aluminum foil works just as well for the job but it lacks conductive adhesive and it is extremely difficult to solder to. Copper tape can be obtained with conductive adhesive so everything overlaps. Additionally, when you buy it online from China the added cost is minimal. Again, do not buy any shielding supplies from Stew Mac, there are much cheaper sources online.

For the OP, there is a bunch of great advice in this thread. I do not have much to add beyond what it said here. Everything I know on the subject, including a simple test to tell if your bass requires shielding, can be read in the link found in my signature. A humming bass is a broken bass in my opinion (outside of single coil noise) so I would shield my bass, even if only playing at home.
 
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#29
Axstar said:
Remember to ground the neck plate while you're at it. :roflmao: Shielding the bridge plate is total overkill. You might find a more robust contact between the bridge and the ground wire if you solder the wire to a section of copper foil under the bridge. Shielding the control plate, if it is metal, is also totally redundant and unnecessary.

OP's bass doesn't have a ground issue. It is noisy until he touches the strings, which means that the ground wire running to the bridge is intact. The detail about touching the strings near the headstock specifically is just additional fluff.

The human body is a good wet, fatty antenna for AC electromagnetic fields. When you take your hands off the strings of an unshielded guitar, the noise is you. The bridge ground wire diverts this signal to ground, shutting you up. Shielding mitigates this issue, but isn't the panacea that some claim. I've found that a shielded instrument is quieter regardless of whether my hands are on the strings or not. I achieved the best results with a MIJ Mustang bass.
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So he should wrap himself in aluminum duct tape? :woot:
 
#30
I only have one active bass that I bought second had and it has the copper shielding. Whoever did it did a stellar job. It's a rear mounted controls cavity. They also did the inside of the controls cavity cover. Not sure if that's necessary or not, but mine is done that way and is dead silent. +1 on making sure the bridge ground is in tact. I think it probably might be because touching the strings kills the hum. Get a little 'lectric meter and check continuity. There's u-tube on how to do this out there. Dave's World of Fun Stuff is a decent resource. He's pretty salty, but knows his stuff.
If part of the problem turns out to be single coil pickup hum, maybe consider changing out to hum canceling ones. It will change the character of the bass tone, so being hum free may be a trade-off. One way you may be able to dodge that bullet that I just thought of is, I remember seeing a Lindy Fralin product demo video and the bass they used had a "dummy coil" in it to get rid of single coil hum. I just told you everything I know about that, so could be another topic for you to research.

Hope this helps!!
 
#32
tlc1976 said:
I've shielded basses with aluminum foil and glue stick. My uncle also shielded his fiddle this way. I realize it's not the true copper foil but it's dirt cheap and readily available. Night and day difference compared to no shielding.
Click to expand...
I learned with this method on a couple of cheap strats early on. Alum. foil and wolfgrip spray did a decent job on them, but for an instrument with any value it is just as much work and a bit more money to use copper. Home Cheapo sells adhesive copper foil for slug repellent. A bit of solder and a star ground, you could be rid of 90% of the hum.
 
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#34
jatremayne2 said:
I learned with this method on a couple of cheap strats early on. Alum. foil and wolfgrip spray did a decent job on them, but for an instrument with any value it is just as much work and a bit more money to use copper. Home Cheapo sells adhesive copper foil for slug repellent. A bit of solder and a star ground, you could be rid of 90% of the hum.
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I agree, if I had a high end instrument, I'd have ordered up the good stuff. Or better yet, pay someone else to do it.

Also at the time I did this, we had no Home Depot, etc. Or internet.

I knew about the HVAC tape but not the copper adhesive foil. I'll check it out one of these days. Thanks for the tip.
 
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#36
tlc1976 said:
I've shielded basses with aluminum foil and glue stick. My uncle also shielded his fiddle this way. I realize it's not the true copper foil but it's dirt cheap and readily available. Night and day difference compared to no shielding.
Click to expand...

Aluminum foil works fine as shielding. But remember the shield must be "grounded" (connected to jack body) to work. The only problem with aluminum foil is that you can't solder to it easily. The standard connect to aluminum foil is a wood screw into the body with lock washer that "bites" into the foil. Pickguards often use aluminum foil and the connection is made by having a foil tab come out of the cavity and goes around one of the pickguard screw holes. Then when you put the pickguard screw in it clamps the guard foil down against the tab to make connection.

But generally I use copper foil that is meant for stained glass window crafts. It is not expensive and has the advantage of already coming with sticky adhesive on the back. And of course you can easily solder wires to it to ground it.
 
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#38
campbems said:
You are seeing alot of builders and bass company's using a special paint that shields the cavities. Does this seem to work as good as the shield tape?
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el_Bajo_Verde said:
The conductive paint was very thin and inadequate. Along with a few other inconsistencies that added to the hum. I'll have it back Wednesday or so.
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When I asked a local guitar tech about shielding paint, he suggested I lay down a coat, let it dry for a day, then lay down another and yet another a day later. I also asked if I should paint it up and over the route's edge to ensure proper contact with the foiled pickguard, to which he said "Definitely!". Overall, the results were perfectly fine.

BlueBody01_zpsdf2063de.jpg


In this case, I used low-adhesive "artists white masking tape" to mask off the overlap's edges. What I didn't do was use any kind of plastic sheeting to protect the rest of the body, a mistake I don't plan on repeating. It seems the paint is incredibly runny and drippy. I only ended up with a couple of drip-spots and fortunately for me, they landed on the black portion of the burst finish.
 
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