Hi! I recently bought a usted Yamaha RBX170, im planning to.replace the pickups and since I'm going to dismantle all the electronics, i want to put shielding on the bass, i've got all the necessary tools, I already bought the cooper tape with conductive adhesive and I have a pretty good idea of how to do It, The problem is that all the online manuals only talk about how to shield basses with a pickguard, and my model doesn't have one, so i was wondering how I should proceed? Should I place the copper tape only in the controls cavity? Or should I also put tape on the pickup cavities even though the Faraday cage will not be closed? On the other hand, on one of the edges of the bass there's a plastic plate where the output jack is screwed, should I also put tape on that plate? Please help this newbie to get rid of EMI induced noise!
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Shielding a bass without pickguard
- Thread starter MikeMonterrubio
- Start date
If you totally close the faraday cage, the the pickup will not work properly. A bass with a pickguard also leave the top of the pickup free.
If you just put tape in the cavity it will be already good because the pickups are by far the most sensitive to emi.
You can always start with the pickup cavity and see how it goes anyway.
Just remember to connect all grounds together (see if there is graphite paint because it will do just that).
Another way, but most costly, is to swap the pickups for a kit of noise canceling ones like the di marzio dp126.
Anyway, if you can post pictures of those cavity, it will be easy to assess what need be done
If you just put tape in the cavity it will be already good because the pickups are by far the most sensitive to emi.
You can always start with the pickup cavity and see how it goes anyway.
Just remember to connect all grounds together (see if there is graphite paint because it will do just that).
Another way, but most costly, is to swap the pickups for a kit of noise canceling ones like the di marzio dp126.
Anyway, if you can post pictures of those cavity, it will be easy to assess what need be done
Copper tape in every cavity. Check for continuity across the cavity. Connect the cavities together with a wire. Connect one of the cavities to ground. Done.
Single coil hum will still be there but no more buzz of the type that goes away when you touch metal on the bass.
Single coil hum will still be there but no more buzz of the type that goes away when you touch metal on the bass.
I had the RBX170 and don't recall, it needed shielding. IME usually shielding is not something a passive control cavity requires if everything is grounded. pickups' cavities might benefit from shielding tho if it's really the interference.
as already noted, you might be hoping to remove the single coil hum with shielding, it won't help. try if you have your 'interference' with the P pickup soloed to see if that's the case.
if you want to shield the control cavity tho, yeah. the proper way is closing the cage, i.e. leaving no unshielded gaps. if I was in your shoes, I'd just stick some tape on the football plate from inside. it should ground itself just with the jack, but using a multi-meter to verify conductivity on your shield is always recommended.
as already noted, you might be hoping to remove the single coil hum with shielding, it won't help. try if you have your 'interference' with the P pickup soloed to see if that's the case.
if you want to shield the control cavity tho, yeah. the proper way is closing the cage, i.e. leaving no unshielded gaps. if I was in your shoes, I'd just stick some tape on the football plate from inside. it should ground itself just with the jack, but using a multi-meter to verify conductivity on your shield is always recommended.
- Apr 18, 2008
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Two different things. Hum-canceling pickups address 60Hz hum, while shielding addresses electrostatic buzz. One is not a substitute for the other.
Electrostatic buzz is still an electric wave that can be cancelled with an humbucking design to revert the noise's phase, basic electric here.
The only other noise that you can have is ground issue, wich is solved with a good grounding.
This is the way to do it.
Conductive paint instead of metal foil will work as well.
Shielded a Heartfield and found the cavities connected by shielding like the ground wire on co-ax guitar cable. And even then the graphite paint couldn't make the multimeter beep
The electronics still have to be surrounded by shielding or there will still be noise. Nothing to do with coil hum or grounding. All my unshielded guitars and basses had noise until I shielded them, despite having hum cancelling pickups and thorough grounding.
if there was no noise, the guitar was shielded. beep or not. sometimes it's hard to make contact with paint, especially when using sharp DMM probes
I highly recommend using a conductive paint for shielding.. it’s a much easier process, and in my experience, it has been easier to get consistent and effective results.
Yes, you shield, the control cavity, I also highly recommend the pick up cavities as well as grounding the pickup pole pieces, if applicable.
it doesn’t always matter, but to shield the wire runs that would normally be under a pit guard, but our instead tunneled through wood, the move is to use a shielded cable or to twist the hot/ground together. If you need to run more than two conductors like for coil splitting whatever, they sell four-conductor shielded wire for humbuckers etc.
edit: Super Shield nickel conductive paint by MG chemicals is what I use for conductive paint. I will never shield a cavity with copper tape again.. I use little tabs of copper tape and ground lug screws for things like connecting sections or making a good sprung Mechanical connection for a cavity cover
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And that’s why I put an extra drop of conductive paint somewhere underneath a pickguard or control plate.
That way, I make sure this little bump will be squeezed and allow for a good contact between a cavity and its cover.
Another trick I found is to steer the paint quite often in the container between applications as solid particles sometimes tend to go down in the container.
A Faraday cage shields against electrostatic interference. You can completely enclose a pickup in copper or aluminum tape, and it will still work because the strings are disturbing the magnetic circuit of the pickup*. i have some Nordstrand built/Dingwall designed pickups that enclose the pickup within copper shielding, and they work just fine. Every Les Paul, SG, 335, and a lot of other Gibson models use pickups that have pickups that are enclosed by a Faraday shield, and they work just fine. There is some impact on the high frequency content, but that's is a well understood thing; that impact can be engineered to be part of the design's performance.
A guitar or bass that doesn't have a pickguard can be shielded just as well as one with a pickguard. Shielding the cavity with copper tape (that is connected to ground), and either a tape strip under the pickup in the cavity, or (if the pole pieces are accessible on the bottom of the pickup) grounding the pole pieces with copper tape applied to the bottom of the pickup (the adhesive has to be conductive for this to work well) will get you there. A lot of modern pickups (Nordstrand does this) will come with the pole pieces already grounded.
There are two sources of noise in guitars/basses. Electrostatic (which proper shielding fixes), and magnetic (which shielding does not fix) - your Jazz Bass with single coil pickups will never be quiet in a magnetic field unless you install hum cancelling pickups. Your old P bass needs shielding to be completely quiet as well in an electrostatic field.
https://www.talkbass.com/threads/jazz-shielding-pictorial-big-images-warning.159191/
Wealth of information in this thread on general shielding.
Wealth of information in this thread on general shielding.
Conductive paint or copper tape will not shield a passive bass completely, as the tunnels carrying wires to/from PUs are inaccessable to these methods.
The most complete solution is:
1/ wrap-shield the PUs, and earth that shielding. Older humbuckers with metal covers do a similar job.
2/ use coaxial cable to shield live wiring. Most modern replacement PUs come with shielded cables specifically for this reason. Anyone noticed?
Been there, done it. It works.
When are manufacturers of "traditional basses" going to wake up and change to modern solutions.? Stop using unshielded wiring ForF***Sake
Convention is holding back innovation.
The most complete solution is:
1/ wrap-shield the PUs, and earth that shielding. Older humbuckers with metal covers do a similar job.
2/ use coaxial cable to shield live wiring. Most modern replacement PUs come with shielded cables specifically for this reason. Anyone noticed?
Been there, done it. It works.
When are manufacturers of "traditional basses" going to wake up and change to modern solutions.? Stop using unshielded wiring ForF***Sake
Convention is holding back innovation.
And I have seen lots of not so much shielded humbucker loaded guitar and bass without noise, actually most of the time, the shield issue pop up about singlecoil instrument. I am still to see a noisy les paul with humbucker for one, even the low ends ones without any graphite paint.
Have you ever tried the same instrument with the same kind of pickup, but one is in nickel plated cover, like a PAF pickup, and one is not? There is a difference.
I am not saying that a faraday cage will make the pickup silent, just that it may cause it to sound differently.
If you're using copper tape you can wind the tape round a mandrel (i.e. wooden barbecue skewer) to form a tunnel which can then be inserted into the holes between the pick ups and control cavity. the copper remains stiff and can be fed through with a little practice. Ensure the tunnel makes contact all around the walls of the shielding you've done on the cavities.
Bridge wire is similar tho I had to drill the hole larger. In this case put the wire through the tunnel you've formed before feeding through.
Why would anyone need to shield the bridge earthing wire???
Yes, I covered that point in my post. I know about eddy currents (the thing that is damping some high frequenchy content in a fully shielded pickup) as I have engineered that effect into multiple products, and I have that modelled in my pickup models that I use for circuit simulations for my basses.
You said: "If you totally close the faraday cage, the the pickup will not work properly". I never said that it didn't affect performance - I stated the opposite. What I was taking exception to is your assertion that it wouldn't "work properly". Gibsons have a LOT of pickups in them that work as they intend them to (which is the definition of "properly", if you ask me)