Grounding my Legacy: WTH am I missing?!

Technical Talk and Tips
akleven
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Grounding my Legacy: WTH am I missing?!

Post by akleven »

I tinker with my guitars a lot, and I admit, I'm not a genius at it, but generally I'm able to get the job done, except for one thing: Once I have removed the ground wire, I can never seem to get the guitar well grounded again.

I have made a few pickup swaps on my Legacy, and I usually disconnect the ground wire so I can just lift out the whole pick guard. But no matter how solid my solder joint seems when I reattach, I still get the old, loud buzz that goes silent when I touch the strings. In the past when I've posted similar problems, I have gotten a lot of questions about the room conditions. The room conditions are not ideal. But there's noting I can do about it, and the bottom line is that of my other guitars, those that I have never un-grounded do not have this problem in the exact same conditions. ALL of my guitars that I have tried to ground myself, including another Strat-style guitar, and a Les Paul, do.

Is there some special magic to grounding a guitar that I am missing? Can anybody help me? I don't want to have to take ALL (or most) of my guitars to the shop over this!

Thanks!
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darwinohm
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Re: Grounding my Legacy: WTH am I missing?!

Post by darwinohm »

I am taking a guess here but it seems like the bridge is not grounded properly and I think you are focusing on the pickups. I would start by laying the guitar on a table, plugged in so you get the buzz. I would then take a piece of wire and ground the bridge plate to the case on the output jack. If the buzz disappears, then check the grounding wire from the trem spring claw and make sure it is grounded to the pickup ground. You can also use an ohmmeter to check these things but there is nothing faster than using a piece of wire and testing grounds. Hope this helps -- Darwin
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Philby
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Re: Grounding my Legacy: WTH am I missing?!

Post by Philby »

If the buzz subsides when you touch the strings, bridge or output jack then your guitar is properly grounded. What you really need is shielding to isolate the electronics from electromagnetic interference, including from your body.

For some reason my G&L's have been the noisiest of all my guitars and have given the best results after shielding. The pick guard material is often uber susceptible to picking up static charge and there is only a small piece of foil on the reverse side in a lame attempt to provide some protection.
louis cyfer
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Re: Grounding my Legacy: WTH am I missing?!

Post by louis cyfer »

Philby wrote:If the buzz subsides when you touch the strings, bridge or output jack then your guitar is properly grounded. What you really need is shielding to isolate the electronics from electromagnetic interference, including from your body.

For some reason my G&L's have been the noisiest of all my guitars and have given the best results after shielding. The pick guard material is often uber susceptible to picking up static charge and there is only a small piece of foil on the reverse side in a lame attempt to provide some protection.

philby is right. you are a big antenna, and the noise that goes away when you touch the strings is you being shielded. a properly shielded guitar, star ground if you want to eliminate ground loops for sure, will reduce this a lot. the 60 cycle hum will remain because you are running single coils. you want to check for continuity wit a meter for grounding everywhere. check between all metal surfaces like bridge, output jack and if there is continuity you have proper shielding.


btw, there should be 2 ground wires to reconnect after lifting the pg out of the guitar.
akleven
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Re: Grounding my Legacy: WTH am I missing?!

Post by akleven »

louis cyfer wrote: btw, there should be 2 ground wires to reconnect after lifting the pg out of the guitar.
Yeah? Usually I disconnect the 2 lines to the jack (one of which is a ground correct?), and line that goes to the trem claw. Is there anything else? Darwinohm above mentioned something about sending a line from the bridge to the jack. That's a new one on me. Have I been doing this wrong all along? I must say, I don't remember there ever being a line like that before. I always thought the jack ground went to the back of the vol pot.

Also, what would you recommend for shielding material? I have experimented with this before with limited success. I live near San Francisco, and there is a gigantic radio tower in the center of the city that just saturates the whole area with radio signal for miles around. :( All the musicians in the area seem to just live with it. Anyway, point being if I'm going to shield there's probably no point in half-assing it. I need to go heavy duty.
louis cyfer
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Re: Grounding my Legacy: WTH am I missing?!

Post by louis cyfer »

Image

shielding should look like this. copper sheeting, not foil and such. i like the aluminum pickguard sheets to combine with this.
akleven
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Re: Grounding my Legacy: WTH am I missing?!

Post by akleven »

louis cyfer wrote:Image

shielding should look like this. copper sheeting, not foil and such. i like the aluminum pickguard sheets to combine with this.
Can't see the pic. Can you re-post? Would like to see.

Thanks.
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Elwood
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Re: Grounding my Legacy: WTH am I missing?!

Post by Elwood »

let's see if I can get it to take,
I was having weird Img posting problems earlier....dunno why

Image

(edit: now the others work ?...maybe earthquake/tsunami related ??...who knows)
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yowhatsshakin
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Re: Grounding my Legacy: WTH am I missing?!

Post by yowhatsshakin »

I only got the pics in the posts to work after I loaded the pic URL in a separate window. Weird ! :think: :think: :crazy:

- Jos
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suave eddie
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Re: Grounding my Legacy: WTH am I missing?!

Post by suave eddie »

I see no pictures. If I 'right-click' on where the photo should be, and choose "open image in new tab", it just brings me to Ron Kirn's website homepage.
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yowhatsshakin
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Re: Grounding my Legacy: WTH am I missing?!

Post by yowhatsshakin »

suave eddie wrote:I see no pictures. If I 'right-click' on where the photo should be, and choose "open image in new tab", it just brings me to Ron Kirn's website homepage.
Hit the quote button on any of the posts containing pictures, copy the URL from between the img tags, open a new brwoser window and paste the URL in there. Only after all of that rigmarole the pictures showed up for me. And they disappear again when that additonal window is closed. Weird!

- Jos
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suave eddie
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Re: Grounding my Legacy: WTH am I missing?!

Post by suave eddie »

Well now the photos are showing..............very strange.
akleven
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Re: Grounding my Legacy: WTH am I missing?!

Post by akleven »

Any insight as to how well this stuff might work? Was in the hardware store today and just grabbed it. Couldn't find copper.http://solutions.3m.com/wps/portal/3M/e ... K3MTXJCBbl
louis cyfer
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Re: Grounding my Legacy: WTH am I missing?!

Post by louis cyfer »

akleven wrote:Any insight as to how well this stuff might work? Was in the hardware store today and just grabbed it. Couldn't find copper.http://solutions.3m.com/wps/portal/3M/e ... K3MTXJCBbl
won't work. you can't solder the aluminum, and it is not intended for electrical conductivity, so you will have a hard time making sure the whole surface is connected. even the copper tape with the conductive adhesive is not nearly as good as just plain copper sheets cut to size and soldered together.