Shielding: Is there a right way and a wrong way?

tubatodd

tubatodd

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Oct 31, 2004
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#1
So I've been slowly working on finishing my "Boogie Bass" which is dedicated to my dog who had passed away in 2015. I recently invested in an EMG J-set pickup kit. Before installing the pickups I figured I'd shield the pickup and control cavities. I purchased copper tape and went to town. After doing the neck pickup cavity I started to develop a technique. The finished result looks pretty damn good for never having done this before.

After I was finished I wondered, "did I do this right?" Which brings me to this thread? Is there a right and a wrong way to do this?

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#3
Looks good, assuming the foil has conductive adhesive.

You will need to solder a wire to the bridge cavity shielding and connect it to the shielding in the other cavity. I also like to have a little bit of a "lip" over a few screw holes so the control plate and the shielding on the underside of the pickguard are also connected.
 
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#8
You need to have "continuity" between all areas, meaning you will need to connect the bridge pickup cavity, bridge, control plate, and output jack ground together. I am a big fan of having a "ground lug" by either using a screw and ring terminals or by soldering directly to the foil like below. You'll see in this installation the neck cavity, bridge cavity, and bridge ground all connected to one point soldered to the foil. Once the electronics were installed, I added other grounds to this point as well.

IMG_2050_zpshvnkyeod.jpg
 
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#9
kalle74 said:
EMG pickups are internally shielded, and they even recommend removing the bridge ground wire. Well done so far, but with the EMG's, not necessary.
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While it is true that the ground wires in the EMG pickups run all along the insulated hot wire in sort of braided net pattern, which means they are basically internally shielded and there's no need for additional shielding, I never heard about them recommending not to use the bridge ground wire.

My EMG Geezer Butler pickups at least came with a small cable join device to connect the bridge ground wire to the ground wire that came attached to the pickup system.

Anyway, my Ibanez Mikro on which I installed the EMG Geezer Butler pickup set is dead quiet, even if not shielded properly, so that part would be correct.

No shielding needed for EMG pickups!

Though, it might still be useful to have your bass shielded in case you later decide to swap for a pair of pickups that doesn't use this internal shielding system.
 
#10
chadhargis said:
You need to have "continuity" between all areas, meaning you will need to connect the bridge pickup cavity, bridge, control plate, and output jack ground together. I am a big fan of having a "ground lug" by either using a screw and ring terminals or by soldering directly to the foil like below. You'll see in this installation the neck cavity, bridge cavity, and bridge ground all connected to one point soldered to the foil. Once the electronics were installed, I added other grounds to this point as well.

IMG_2050_zpshvnkyeod.jpg
Click to expand...

I would cut that long wire short and solder it to the foil, right next to the hole that it is coming out of.
 
#11
tubatodd said:
So I've been slowly working on finishing my "Boogie Bass" which is dedicated to my dog who had passed away in 2015. I recently invested in an EMG J-set pickup kit. Before installing the pickups I figured I'd shield the pickup and control cavities. I purchased copper tape and went to town. After doing the neck pickup cavity I started to develop a technique. The finished result looks pretty damn good for never having done this before.

After I was finished I wondered, "did I do this right?" Which brings me to this thread? Is there a right and a wrong way to do this?

View attachment 1102588 View attachment 1102589
Click to expand...

That looks good. Lots of great advice in this thread so I will just echo some of it. I always bring the copper/paint out of the cavity so the shielding makes contact on the guard/control plate. You will need a wire to ground the pickup cavity. You will also need wires to run to the pickup covers should you chose to do them. I find most basses need them done in order to get fully silent. If you decide to do them, I just tape the covers in a certain way that they get grounded out as they are screwed in, you can see this in the thread linked in my signature. While not necessary, I would also recommend adding some copper tape under the bridge to ensure better contact with the ground wire.
 
#12
DiabolusInMusic said:
That looks good. Lots of great advice in this thread so I will just echo some of it. I always bring the copper/paint out of the cavity so the shielding makes contact on the guard/control plate. You will need a wire to ground the pickup cavity. You will also need wires to run to the pickup covers should you chose to do them. I find most basses need them done in order to get fully silent. If you decide to do them, I just tape the covers in a certain way that they get grounded out as they are screwed in, you can see this in the thread linked in my signature. While not necessary, I would also recommend adding some copper tape under the bridge to ensure better contact with the ground wire.
Click to expand...

Shielding pickups is generally not recommended. (Although pickup cavities should always be shielded.) When you shield a pickup coil, it changes the flow of Eddy currents, causing the pickup to sound different. For example, it's a well known fact that Gibson style humbuckers on guitars sound warmer when they have metal covers, than when they are "naked."
 
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#13
line6man said:
Shielding pickups is generally not recommended. (Although pickup cavities should always be shielded.) When you shield a pickup coil, it changes the flow of Eddy currents, causing the pickup to sound different. For example, it's a well known fact that Gibson style humbuckers on guitars sound warmer when they have metal covers, than when they are "naked."
Click to expand...

This is true, that is why I said "if you decide to do them" as many do not shield pickup covers for that exact reason. I suppose I could have been more clear with my post. While I often hear this, I have never noticed an impact on my tone from shielding. I have, however, noticed the lack of additional noise so I feel it is more than worth it. Additionally, many manufacturers will shield their pickups prior to potting them into epoxy, such as Dingwall, so I don't think it is a completely bad idea.
 
#14
DiabolusInMusic said:
Additionally, many manufacturers will shield their pickups prior to potting them into epoxy, such as Dingwall, so I don't think it is a completely bad idea.
Click to expand...

It depends entirely on what kind of tone you are after. If a manufacturer is designing a pickup to sound a certain way, then no one is going to complain. If someone does something that changes their tone, however, then they may not like it, even if it sounds better, just because it isn't exactly the same as before.
 
#15
tubatodd said:
So I've been slowly working on finishing my "Boogie Bass" which is dedicated to my dog who had passed away in 2015. I recently invested in an EMG J-set pickup kit. Before installing the pickups I figured I'd shield the pickup and control cavities. I purchased copper tape and went to town. After doing the neck pickup cavity I started to develop a technique. The finished result looks pretty damn good for never having done this before.

After I was finished I wondered, "did I do this right?" Which brings me to this thread? Is there a right and a wrong way to do this?

View attachment 1102588 View attachment 1102589
Click to expand...
yes.
 
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#16
DiabolusInMusic said:
That looks good. Lots of great advice in this thread so I will just echo some of it. I always bring the copper/paint out of the cavity so the shielding makes contact on the guard/control plate. You will need a wire to ground the pickup cavity. You will also need wires to run to the pickup covers should you chose to do them. I find most basses need them done in order to get fully silent. If you decide to do them, I just tape the covers in a certain way that they get grounded out as they are screwed in, you can see this in the thread linked in my signature. While not necessary, I would also recommend adding some copper tape under the bridge to ensure better contact with the ground wire.
Click to expand...

I don't recall where, but I remember reading that you shouldn't carry the foil out of the cavity. You should only have one contact point so as to reduce the possibility of ground loops. I don't know if it's probable or not but it made sense to me.
 
#17
Renaissance said:
I don't recall where, but I remember reading that you shouldn't carry the foil out of the cavity. You should only have one contact point so as to reduce the possibility of ground loops. I don't know if it's probable or not but it made sense to me.
Click to expand...

In a passive extremely low current setup such as a guitar or bass, a single grounding point or "star" arrangement is completely unnecessary and just makes for a lot of extra wires in the control cavity. I wouldn't bother doing that. If you've shielded the cavities properly and grounded what needs to be grounded like most passive instrument wiring schemes do it (i.e. to either the pot casings or the jack's ground lug), you'll be fine.

This is a handy little trick from Breja Toneworks for handling grounding wiring that I use all the time:

 
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#18
40Hz said:
In a passive extremely low current setup such as a guitar or bass, a single grounding point or "star" arrangement is completely unnecessary and just makes for a lot of extra wires in the control cavity. I wouldn't bother doing that. If you've shielded the cavities properly and grounded what needs to be grounded like most passive instrument wiring schemes do it (i.e. to either the pot casings or the jack's ground lug), you'll be fine.

This is a handy little trick from Breja Toneworks for handling grounding wiring that I use all the time:

Click to expand...


Very cool! Thanks.
 
#19
Renaissance said:
I don't recall where, but I remember reading that you shouldn't carry the foil out of the cavity. You should only have one contact point so as to reduce the possibility of ground loops. I don't know if it's probable or not but it made sense to me.
Click to expand...

You cannot get a ground loop in a bass. There is a lot of miseducation floating around on the internet.
 
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#20
NoiseNinja said:
While it is true that the ground wires in the EMG pickups run all along the insulated hot wire in sort of braided net pattern, which means they are basically internally shielded and there's no need for additional shielding, I never heard about them recommending not to use the bridge ground wire.
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it says so in all their install manuals and has for decades now.

there's no sonic harm in leaving the string ground, they just suggest you don't need it and it reduces the risk of getting shocked by a badly grounded mic or whatever.

as for the foil, make sure it's all connected to ground, but get it too close to the pickup coils and it can dull the tone from eddy current loss.

that's why you don't want to say line the covers themselves with grounded foil.
 
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