Will copper shielding fix a ground buzz?

[Chuck H]

The shielding obviously does kill the high frequencies. You "could" measure the capacitance of the shielding, with a meter.

Tell me, what are the test points for this? The shield and the guitar output?

SGM, try to consider what you are saying before you continue. There is no significant current in the pickup coils for cavity shielding to cause shared inductance and there is too much distance between cavity shielding and any components or their leads to cause a capacitance affecting audio frequencies. Your principals are sound but they don't apply in this case because of it's particulars. When you see the color red you know it's red, but a red car isn't principally red. It's principally a car. Stop creating theoretical arguments that ignore some aspects of the issues at hand. It's antagonistic and harshes my mellow on a Saturday morning.

[soundguruman]

There are an infinite amount of players with single coil pickups,
and they will pay $$$ to have their guitars "shielded."

But will this make a single coil pickup stop buzzing?

No.

Will this make a lot of money for people who install "shielding" inside guitars?
Yes.

So, you can see where the underlying motivation is coming from...

Single coil PU will always buzz and hum, no matter how much "shielding,"
and no matter how much you "think" it's going to stop the problem from happening.

That's cause there is no problem, to start with.

As long as you live in a world with AC electricity...single coil pickup will buzz.

Gullible, unlimited.

[Chuck H]

I generally agree with you. But the shielding does help a little. Copper by itself even without grounding will present some EMF shielding. And we're after every improvement we can get. The principal problem is that the coils are sticking most of the way up and out of any shielded cavity.

[Jazz P Bass]

Big Tee, the trick is to not read his posts.

I believe you will feel better if you don't.

[big_teee]

Big Tee, the trick is to not read his posts.

I believe you will feel better if you don't.

Thanks for that, and you are correct, I'll try not to do it again.
I try to be nice to others, but he just wants to be a Troll, spreading Nonsense, hate and discontent!
Also, don't forget there is the member Ignore List.
T

[Tom Phillips]

I recently did a major mod to my guitar...now it has developed a small ground buzz (a buzz that goes away when I touch any metal on the guitar)...

Consider this: The buzz goes away when you touch the metal of the guitar. What’s up with that? You did not change anything in the guitar by touching it but you did ground your body and that allowed the noise that your body was picking up from the electric fields in the room and re-radiating to the guitar to bleed off to ground. If the guitar is quiet enough for you when you are touching it then maybe all is good.

Here is an experiment that you can try. Prop up the guitar on something non conductive. Connect the guitar to your amp and set the controls as usual. Stand close to the guitar and find a position that gives you the same buzz effect when you touch / don’t touch the metal on the guitar. Now walk away from the guitar. If the buzz diminishes as you walk away then it demonstrates that guitar is picking up the noise field from your body.

What can you do about it?

1. Maybe you don’t need to do anything now that you understand the physics behind the situation. As I noted earlier if the guitar is quiet enough for your purposes when you are touching it then just play and enjoy.
2. If it really bugs you then maybe additional shielding will help. However, shielding the cavities will only reduce the buzz energy making its way through the body of the guitar to the wiring and controls. If the buzz getting in directly through the pickups is still significant then that remaining buzz could overwhelm the improvement you get by shielding the cavities. In that case you are back to #1.

Cheers,
Tom

[g1]

I'm wondering if someone's meds run out every weekend. That seems to be when the inane posting rampage begins weekly.

[Chuck H]

Everything is futile! Consider that our current maths and sciences can't properly explain an infinite area. It's theoretically impossible. Since we exist within one, we aren't.

Here's another... If you drop an object it will never reach the ground. And I can prove it too. The object must first travel half the distance, then half of the remaining distance, then half the remaining distance, etc. Since the distance it will travel can always be divided in half there is an infinite number of halfway intervals to be traversed and the object never reaches the ground. By this logic nothing ever happens and none of us have ever come to be. Therefor we aren't.

Logic is futile.

[Jazz P Bass]

.
Also, I forgot, but you can mark a member to not read their posts.
It's called the Ignore List, I just put him on it!

I didn't know about that.
Thanks.

[bjfly17]

I really appreciate all the response to this thread, but for the sake of my poor guitar, I'd like to direct us back on track. Here is an overly detailed post of my mod. As everyone here obviously has faith in their own abilities, I'd love to submit this project to you guys and (if anyone has the time/kindness) hopefully someone can work out where there is room for error.

What I did: Modded my ESP with a set of JB/Pearly Gates humbuckers to a 2 Humbuckers/3-Way Toggle Switch/1 Volume/2 Tones/Coil Tap & Series Parallel. Guitar Wiring Diagram 2 Humbuckers/3-Way Toggle Switch/1 Volume/2 Tones/Coil Tap & Series Parallel
On top of the tone mods, I also used a push pull pot on my volume to wire a kill switch Wiring Diagram
And topped it off with a simple treble bleed circuit on the volume knob Guitar Wiring Mod-Volume Treble Bleed-Bypass Circuit w/ Parallel Resistor

For reference, here are the Seymour Duncan color codes for my JB/Pearly Gate setup: Guitar & Bass 4-Wire Humbucker Color Code Diagrams

Using four conductor wire and cloth push back wire, here are some pictures of the final job with short descriptions:

View of switch cavity. Down goes to neck - pot 1.


Detail of Pot 1 - neck tone. Includes the 4 conductor wire running from the neck pickup.


Detail of Pot 2 - bridge tone. Note that the electrical tape is covering a joint I had to make to accommodate the schematic. Splitting the black conductor into two separate wires.


Detail of Pot 3 - master volume. Includes kill switch and treble bleed with parallel resistor.


Connection from jack to Pot 3. For the killswitch, I had to double wire it.

Next three are attempts at capturing the grounds on the back of each pot. Pardon the solder, when I first discovered my ground buzz, I reapplied generously to try to fix it. This includes the ground for all wires, capacitors, pot-to-pot grounds, and pot-to-bridge (pot 3).


(I had to post the last picture in the next post.)

I realize this is a lot, and the pictures may not be super helpful - I am only hoping that there may be someone here who truly knows their stuff and can spot an error either in my physical work or the combination of the mod circuits.

Ignore the attached thumbnails.

Thanks in advance guys!

[bjfly17]

Final ground picture (pot 3):


Summary:

Basically, I truly believe the buzz is coming from a ground fault and I am doubting that shielding will remove it - as I've heard that it would only help with hum or interference. But I am willing to give it a shot.

I am not sure if anyone can spot any causes for this in the pictures, but I am hopeful. Additionally, there are a few aspects which I would like to point out:
1) I removed the old tape from my humbuckers and used common electrical tape in its place. Is this okay?
2) Would the coil split mod introduce buzz that is typical to single coil setups?
3) I had to create joints for each individual conductor coming from the pickups to extend the wire to the cavity. Then wrapped in electrical tape. I also had to create a similar joint on pot 2 to extend the black conductor into 2 separate leads.
4) Are cloth push back wires sufficient for shielding purposes? I assumed so...
5) I soldered the tabs on pot 3 directly together to avoid short wiring runs. I know this is common in some cases, but didn't know if it would negatively influence the kill switch on my push pull pot.

Just some thoughts to try to pinpoint where I went wrong.

[Chuck H]

Lemme ask... Does the guitar do this in ALL the pickup selections? It seems you've added a bunch. I've been through as many custom guitar wirings as anyone and I can tell you for certain that the more elaborate you get, the greater the likelihood of noise in some of the selections. If you touching the guitar is grounding out the buzz then it's very unlikely you have a mistake in the selection wiring. The only four possibilities I can think of are:

1) The guitar isn't making a proper connection to the shield terminal on the output jack. Not likely since I don't think a human body has enough ground potential to entirely squelch the noise without, itself, being grounded.

2) As suggested, YOU are an antennae and touching the guitars ground grounds you. Quite likely if the problem exists mainly with the pickup selections you didn't have before OR with the Pearly Gates, which is a little asymmetrically wound IIRC.

3) The problem exists only on certain pickup selections because you now have elaborate wiring that allows non hum cancelling selections AND you are an antennae.

4) Your guitar cord or input jack on your amp isn't grounding your guitar. Try a different cord and amp. Not likely the cause but can easily be ruled on.

If you have phase, series, parallel and coil tap switching there is also the possibility of a coil floating in one or more pickup combination selections. I wouldn't expect touching the guitar to ground that out though.

It's virtually impossible to decipher what's happening in your guitar by looking at the pictures. A schematic is absolutely necessary to determine if the circuit may be responsible. This ignores the possibility that there is a mistake in how the circuit was wired.

[bsco]

Hey there big_teee.....I didn.t know there was an ignore list.....he has insulted me on a few occasions as well....Think I'll add him to that list......all he does is put everybody else down.......he is always right and everybody else is wrong....the funny thing is...it is usually the other way around...

[big_teee]

If I read the photos correctly this wiring method will not work without noise.
I only see push back wire going to and from the 3 way switch, no shielded cable.
You can not run un-shielded wire from the control cavity, across the pickup hole routs to the switch unshielded, and back.

[Tom Phillips]

...Are cloth push back wires sufficient for shielding purposes? I assumed so...

N0. The cloth push back wire shown in your photos provided no shielding at all. It is just single conductor insulated wire.