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Tracking the buzz...


Jazzer2020

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I fall victim to guitar buzzes every once in a while...

 

This time it's a Gibson ES-175 archtop, single P90 pickup.

 

I made good progress a couple of days ago.

The buzz is coming from inside the guitar.

It happens only when certain notes/chords are played.

 

When I push a finger inside the fretboard side of the bottom F-hole and apply some pressure

to the wood, the buzz stops!

 

I haven't pulled anything out from the guitar yet and would like some tips on how to proceed next

to pinpoint the source and fix it.

 

Thanks!

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I'd get in there with a good light and a small mirror and look for anything loose; binding lifting' date=' structural issues, or even [b']the wire harness vibrating against the wood[/b].

 

That's my thought as well - although when I saw buzz and P90 in the OP...

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You can get little wire hold down things that are a piece of soft metal with a sticky back and a little metal tab. I get several each time I install an acoustic pickup - they come with the kit but I assume you can buy them in a hardware store. You bend the little tab over the wire and just stick it in place. Much better than using a wire tie which would be hard to remove.

 

Someone will have a name and link

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You can get little wire hold down things that are a piece of soft metal with a sticky back and a little metal tab. I get several each time I install an acoustic pickup - they come with the kit but I assume you can buy them in a hardware store. You bend the little tab over the wire and just stick it in place. Much better than using a wire tie which would be hard to remove.

 

Thanks Freeman. So you would opt for taping down the wire to the wood top rather than trying to get the wire to float inside away from the top?

 

 

 

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Thanks Freeman. So you would opt for taping down the wire to the wood top rather than trying to get the wire to float inside away from the top?

 

 

 

Either way would work - if I have very long runs of wires inside guitars I try to stick them down

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Either way would work - if I have very long runs of wires inside guitars I try to stick them down

 

Thanks Freeman.

I haven't gotten around to taping the wire down yet, but I was just playing the guitar and noticed something else.

This is through a small Fender tube amp.

 

In addition to the wire buzzing when those notes/chords are played, there is a nasty hum (high pitch) happening as well.

As soon as I put my finger inside the F-hole and touch the wire the hum goes away almost entirely.

 

Would you know if I tape the wire to the top if this hum will go away (ground hum)?

Or will I need to do something else?

 

 

 

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That sounds to me like a loose ground connection, very likely a cold solder joint, or possibly when the wire is floating free it is touching something but not when you push it down. Just taping it down will not fix the loose connection or cold solder joint, but if its just touching it could. A small inspection mirror and flashlight might help you see but it will be hard to tell just looking thru the f-hole.

 

I think you probably should pull the wiring harness out and inspect and thats a real PITA for an f-hole guitar. Single pickup would be easier but its still a hassle. What I do is tie a little string (I use dental floss) on the shaft of each pot and the jack (switch, but you won't have one), as you pull the harness out leave the strings extending out thru the holes so you can get them back.

 

Good luck

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in most guitars the strings are grounded and when they are touched your entire body gets grounded and collects the AC waves before they get to your electronics.

 

Typically Gibson guitars are wired very well with little chance of messing up on their own. If the guitar is stock I doubt there is an issue with the harness itself. If someone has modded the pickup then all bets are off, it could be a botched solder job.

 

The things that do tend to give you problems is the output jack can get loose and once that happens the wires can fray through constant movement. The nut should be tightened if its loose. The Nuts on the tone and volume can loosen, allow the pots to spin, and mess up the wires going to them. Again, whether there's permanent damage from being loose for a long time is questionable. Gibson typically uses the highest quality wire and causing any of the connections to go bad would be unlikely.

 

When you reached inside you may have grounded the shielding which lowered the hum. This is usually done by the tail piece being connected to a ground wire. Its possible the screws and strap button have become loose and no longer make contact with the bare wire that's between the body and the tailpiece mount. The wire isn't soldered, its just the pressure of the tailpiece being screwed down against the wire that makes a contact.

A loose tailpiece mount can cause a bad ground.

 

The other thing that can cause a problem are the ball ends of the strings. D'Addario, Labella and a few other string manuAfacturers paint the ball ends to make the strings easier to identify the gauges when installing them. The problem with that idea is it makes for a crappy string ground and touching the strings may not provide a good enough ground to completely reduce the hum. You could try some sand paper to remove the paint from the ball end but you risk damaging the strings. What I do is take an unpainted set of balls from an old set of strings and cut them off. Then I slide them onto the new strings before installing them. This gives you a second set of balls (That would be something) at the string end which touch the string and make a reliable contact.

 

I've also seen older tail pieces get tarnished badly where the string ball sits thus making a poor ground contact for the string. A little fine sand paper or a nail file can be used to remove the tarnish and shine the metal to get a solid contact.

 

Also coated strings like Elixir and others can be a big problem, at least on the lower strings. The coating is a non conductive epoxy that insulates your fingers from providing a solid ground. Only the unwound, uncoated strings would be able to provide a ground in that case and that can make for some nasty hum playing notes on the rest of the strings.

 

As far as tacking down the wires, I typically use a drop of hot glue. Its fast, its easy and it doesn't permanently bond with the wood so you can peel it off if needed. In a tough to reach spot, you simply use a piece of coat hanger shaped to where it will reach the spot you need, then place the drop to the wire then fish it into the spot you need and tack the wire in place. I've seen manufacturers include a putty that remains soft for tacking wires too. I found the hot glue best because it doesn't leach oils into the wood.

 

 

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Thanks Freeman and WRG for your help!

OK today I decided to bite the bullet and open her up.

 

I believe I spotted the problem but would like your expert opinion on what my next steps should be.

 

I will upload a photo so you can see what looks to be the problem.

I think everything is original and massively corroded.

 

I cleaned off the bottom of the pickup but these pots look like they should be changed.

I see a huge cap and one end has come unsoldered.

 

If you recommend I change the pots and cap please let me know and also a good wiring diagram would be helpful.

This is an ES-175 single PU, 1953.

If I should change them I'd probably order from Stew-Mac.

I'd need to know the pot values and the cap type/value.

 

Also, if I change them, could I use the existing PU wire or should I also order another PU wire?

 

The ground wire connection looks OK, but I guess if I change the PU wire I'd have to resolder it to the new one.

 

Thanks!

 

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Put a piece of cardboard under that! :cop:

 

Looks like a very cool guitar.

 

 

Yeah I was careful with the heavy pickup not to lay it on the body but not as careful with the pots. :(

I've got a boatload of guitars, but this one is definitely the sweetest of them all. :)

 

 

 

 

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I'd ask around for the best repair person near you and get it perfectly rewired. For a great guitar like that the cost is justified and it's likely to sound better.

 

Thanks. I was thinking the same.

I've done re-wiring and soldering stuff in the past, but I'm certainly not a pro at it!

You are right, for a guitar like this I'd rather have it done perfectly.

 

BTW, what's your take on that cap?

I don't know what they used exactly back then.

 

StewMac has an assortment.

The closest looking one they have is an Emerson I think, paper-in-oil.

 

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I'm not an expert on caps. I was told years ago that the only thing that makes a difference with caps is how close they actually are to their target capacitance and how long they stay that way in a guitar environment.

 

Would be interesting to know the value of the existing one and it's rating.

 

If you do refurb the wiring make sure you keep the original wiring intact so you can put it back to stock if you want.

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I'm not an expert on caps. I was told years ago that the only thing that makes a difference with caps is how close they actually are to their target capacitance and how long they stay that way in a guitar environment.

 

Would be interesting to know the value of the existing one and it's rating.

 

If you do refurb the wiring make sure you keep the original wiring intact so you can put it back to stock if you want.

 

 

Thanks Grant.

That's a good idea to keep the original wiring should I go ahead with a refurb.

Right now we've got holidays here and there isn't anyone good local to do the job that I know of, so I'll wait until next week to

decide my next move.

 

 

 

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OK this is going to be a really tough one I fear.

When I opened her up and unscrewed the screws from the tail-piece one of them came out really short,

like two or three threads only. I quickly saw that the screw had broken and only its head came out,

with the body of the screw remaining in the wood.

 

Has anyone ever had to deal with a problem like this before?

And we are not talking about an accessible hole here.

It's a hole accessible only from the outside of the guitar and it's plugged with a broken screw that

is flush with the outside.

 

Any elegant ideas on how to get that broken part of the screw out?

 

 

 

 

 

 

 

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OK this is going to be a really tough one I fear.

When I opened her up and unscrewed the screws from the tail-piece one of them came out really short,

like two or three threads only. I quickly saw that the screw had broken and only its head came out,

with the body of the screw remaining in the wood.

 

Has anyone ever had to deal with a problem like this before?

And we are not talking about an accessible hole here.

It's a hole accessible only from the outside of the guitar and it's plugged with a broken screw that

is flush with the outside.

 

Any elegant ideas on how to get that broken part of the screw out?

 

 

 

 

 

 

 

There are special tools for screw extractions. It really depends on how small the screw was.

You have some which screw in around the screw like this.

[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"BoatBuildersSet.jpg","data-attachmentid":32523714}[/ATTACH]

 

Or this

 

[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"OUVFrJHRltvWoDlg.medium.jpg","data-attachmentid":32523712}[/ATTACH]

 

You also have the type that bore into a screw.

 

[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"71GBPVhMDCL._SX425_.jpg","data-attachmentid":32523713}[/ATTACH]

 

 

In most cases its not a pretty job even with the proper removal tool.

I've done some on guitars where the screws were glued in and busted the heads off trying to get them out. I filed a notch for a flathead screwdriver, then heated the screw wit a soldering iron long enough to burn the wood and eventually get the screw to spin. It was neither fun nor pretty. I eventually plugged the hold and re-drilled a new hole for the proper screw. Most screw extractors do collateral damage if there is no screw above the surface. If there is you can typically use a good set of plyers to grip the end and rock the screw turning in each direction till it begins to spin. Again, heat can help here.

 

Some of the metal used for screws for guitar hardware can be really bad. Some are too soft and strip the heads, Others which are harder can crack or bust a head off like yours did. Guitar woods can be very hard and unless the holes are pre drilled you can run into problems removing or installing them.

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There are special tools for screw extractions. It really depends on how small the screw was.

 

You also have the type that bore into a screw.

 

[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"71GBPVhMDCL._SX425_.jpg","data-attachmentid":32523713}[/ATTACH]

 

 

In most cases its not a pretty job even with the proper removal tool.

 

You're right WRG it wasn't a pretty job!

 

I went to a couple of hardware stores and ended up buying the 'bore into screw' type.

It was a special 'mini' bore size tool set.

But even the smallest bore was still too big for the screw!

 

I ended up drilling a bunch of holes around the screw, and eventually after a lot of drilling

and filing I was finally able to get a pliers around the screw and unscrew it!

 

Next I used wood fill to fill up the hole. Then sanded the top of the fill and drilled a new hole for the new screw.

It worked!

But again it wasn't pretty.

 

 

 

 

 

 

 

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