Shielding making things worse?

[Guitarist]

Today I confirmed what I thought was the problem with two guitars. They're fully copper shielded and star grounded. But compared to another stock guitar I have—which is quieter noise wise—these are capturing ambient buzz and higher frequency hash somehow.
Should I lift the shield with a cap or disconnect it entirely?

Bridge is string grounded.
Kinda sucks to be rewarded with a step back.

[soundguruman]

Today I confirmed what I thought was the problem with two guitars. They're fully copper shielded and star grounded. But compared to another stock guitar I have—which is quieter noise wise—these are capturing ambient buzz and higher frequency hash somehow.
Should I lift the shield with a cap or disconnect it entirely?

Bridge is string grounded.
Kinda sucks to be rewarded with a step back.

It really comes down to the pickups.
Putting a bunch of shielding in a guitar does not (generally) produce squat.
Now, I'm guessing you have single coil pickups, or you have humbucking pickups wired wrong.
But there is no shielding that will stop a single coil pickup from buzzing. Dream on, it won't happen.
So tell us what pickups you have, and what guitars, etc...then we will tell you what pickups you "should" have.

[Guitarist]

Hi and thanks for replying. I've done the GuitarNuts thing quite a few times, star grounding etc. These three guitars are all humbuckers and one DiMarzio Area. I'll add a quick recording soon. It may be that I added a piezo disk on the two problematics, but they're wired to the sleeve (stereo) —I'll disconnect them as the cool dobro tone is too quiet anyways. Other than that the grounding work is pretty sweet and star grounded.
It sounds like the shielded noise is making its way in to the pickups grounds somehow before it hits the far end of the cable...?

[DrGonz78]

So the copper shielding is truly grounded? Have you tested to confirm this using a DMM?

[soundguruman]

Hi and thanks for replying. I've done the GuitarNuts thing quite a few times, star grounding etc. These three guitars are all humbuckers and one DiMarzio Area. I'll add a quick recording soon. It may be that I added a piezo disk on the two problematics, but they're wired to the sleeve (stereo) —I'll disconnect them as the cool dobro tone is too quiet anyways. Other than that the grounding work is pretty sweet and star grounded.
It sounds like the shielded noise is making its way in to the pickups grounds somehow before it hits the far end of the cable...?

There two or three things,
The piezo will hum like a kazoo.
humbucking pickups, with unbalanced coils, will hum a lot. And so will they that have the coils incorrectly phased.
Shielding, to compensate for hum in a guitar, is for all purposes, just about completely useless.
The hum comes from the pickups, folks. So no matter how you shield it, or what the shield connects to, will give you just about nothing.

[David Schwab]

Hi and thanks for replying. I've done the GuitarNuts thing quite a few times, star grounding etc. These three guitars are all humbuckers and one DiMarzio Area. I'll add a quick recording soon. It may be that I added a piezo disk on the two problematics, but they're wired to the sleeve (stereo) —I'll disconnect them as the cool dobro tone is too quiet anyways. Other than that the grounding work is pretty sweet and star grounded.
It sounds like the shielded noise is making its way in to the pickups grounds somehow before it hits the far end of the cable...?

I have read a number of times over at TalkBass, where someone did the GuitarNuts thing and the noise got worse.

You don't need star grounding in a guitar, and putting the cap between the shield and ground is stupid. Also you will not get a ground loop connecting the pots together. That wole article makes a lot of erroneous assumptions.

Wire the guitar up the normal way. make sure your shielding is grounded, as well as the backs of the pots (which is shielding), and your noise should go away.

[soundguruman]

And I think checking the phase of the pickup coils could possibly help.
There could be coils reversed or incorrectly connected.
It might help to try reversing the coils, one at a time, to see if there is better hum cancellation.

If there is no power / earth ground, to the amplifier, that can be a problem.
It is not bad to buy a tester like this to confirm your power ground.
Wire Outlet Tester - Sperry Instruments - Mfg# GFI6302

[big_teee]

Don't forget the Amp, room 60hz noise and Gain.
Some High Gain Amps are a lot noisey than Others.
Some Combos are more Noisey than Head type Amps.
It's the total Package that has to be looked at.
T

[soundguruman]

Yes, but don't forget the PU is the source of the 60 cps noise which is amplified.
Start at the pickup.
Once the PU has absorbed 60 cps, there is no shielding on earth that will stop it (the noise) from being amplified.

When this shielding first appeared, it was "stick on" aluminum foil. Useless.

Where does the 60 cps come from? The amplifier power transformer.
The field around the transformer is sucked up by the pickup. Move AWAY from the amplifier.
OR, put better shielding on the power transformer casing, like MU metal...
Where else? Fluorescent light transformers, or any device that has a 60 cps field around it...

Normally, when we see this kind of problem:
A. The power ground is missing or defective, wired wrong. The user assumes that the ground is GOOD, and NEVER checks it.
But keeps complaining about the noise....AND NEVER BOTHERS TO CHECK IT (that's YOU! bud.)
You COULD invest $10 in a ground tester, but you WON'T. Because you are running on assumptions, not facts. Continue to wallow in ignorance, if it pleases you.
B. The fluorescent light transformers are not grounded. (which of course, you NEVER check)
C. The fluorescent lights have dirty, arcing, burning pins on the lamps. (which of course you NEVER check.)
D. The coils of the pickups are out of balance, or the phase of one coil is reversed.

[big_teee]

If you have enough gain they all get noisy, unless you are playing an amp with a noise gate.
As far as balanced pickups, I've made a lot asymmetrical pickups with one coil with more winds (usually the slug coil).
Not much worse than a regular pickup. Unless they are severely unbalanced.
High gain pickups pick up more noise. The pickup doesn't create the noise it just transfers the noise to the amp.
If you can cure a lot of the noise at the source, that is a great place to start.
Don't play on top of the amp, the Transformer in the amp is the main 60hz source of the amp.
Play several feet a way and to the side of the amp.
Not a foot or two in front of the speaker. Unless you like the noise.
**
If you are having Microphonics, or lots of Feedback, that could be another issue, and the Pickups may need to be wax potted.

[soundguruman]

Big T is right you gotta get away from the amp...

[David Schwab]

Once the PU has absorbed 60 cps, there is no shielding on earth that will stop it (the noise) from being amplified.

We are talking about two different noise sources here. Single coil pickups are sensitive to magnetic field noise. Shielding doesn't help that much, but humbuckers take care of that.
The other stuff is electrical field noise. Humbuckers can't help with that, but shielding does.

Some noise, like from light dimmers, very hard to get rid of.

Amps often hum from the power supply noise getting into the signal. Some clubs and bars are just noisy.

A well shielded, hum canceling pickup can be dead quiet in 90% of situations.

[DrGonz78]

There two or three things,
The piezo will hum like a kazoo.

There so many things here since we all just keep posting but the OP has gone Xmas vacation till Easter!! Holy Jesus!! Anyway looking at this post it became more clear to me that the hum was not caused by shielding, not by humbuckers/single coil pickups, not by 60 hrtz alone...

"It may be that I added a piezo disk on the two problematics, but they're wired to the sleeve (stereo) " Now there have been MANY posts here to this thread but yet the OP has yet to return... I hate waiting so long for something other than just advice to someone that goes silent.

Edit: Are you using shielded wiring??