Hum in my 62 335.

[Mike M]

I am having some issues with my new purchase. I just bought a 1962 335 Bigsby. 1 PAF in the neck, and Pat# in the bridge. It has an extremly loud hum. I touch the strings, jack, and other areas, and it goes away. My question is, Is this typical of older pickups? I am not the best when it comes to electronic fixes, and pulling the electronics out of a 335 is like doing brain surgery. Would there be an easy way to determine what is causing the hum? A trick I have learned is when I rest the bigsby arm on the guitar cable coming out of the jack, the hum goes away. I was wondering if the bridge is not properly grounded. Any help would be appreciated. I want to hear the true PAF tone without the hum. It is starting to piss me off.
Thanks

 

[plaintop]

You might need to send that one right over to ME. :lol

Sounds like a grounding issue.

 

[LesPauloholic]

A lot of times there is a ground wire that comes out a hole near the endpin underneath where the bigsby is bolted to the guitar. That ground wire is "smashed between the bigsby mounting brackit and the guitar body. Maybe at some point the bigsby was removed for cleaning and the wire was pushed back inside the guitar. If you have an ohm meter you can make sure the bigsby (or abr-1) is grounded. Put one lead on the bigsby and one on the nut of the output jack, or a pickup cover. If that is not 0 ohms (or darn close) try the abr-1 to the jack nut or a pickup cover.

Good Luck.
Greg

 

[Mike M]

Greg

Thanks for the info. Are you talking about where the bigsby is bolted near the strap button, or underneath on the face of the guitar? I recently cleaned it when I received the guitar, and I saw no wire. Maybe thats it.

 

[LesPauloholic]

On the butt end by the strap button.

Greg

 

[Mike M]

Greg

I just removed the Bigsby, and the was no wire present. I can see a wire inside of the f hole that is drilled towards the bridge. Do you think they grounded the bridge that way? All your help is appreciated.

Thanks

 

[LesPauloholic]

You can drill a hole that intersects the hole that your bridge posts are screwed into. Run the wire Through that hole, then tighten down the bridge post screw down on it. To see if this has been done. Get an ohm meter and measure between the bridge and one of the pots, or the output jack. If it's 0 ohms it's connected, if not... buzzzzzzzzz

 

[Wilko]

I wouldn't go drilling around looking for ground wires before checking the harness. A good harness won't hum, even with no bridge ground.

 

[LesPauloholic]

I wasn't suggesting he should go drill....

I was trying to explain (maybe not clearly enough) that the factory might have done it this way.

On a Bigsby equipped guitar the two ways I know of to ground the strings is either to run a ground wire out the butt end of the guitar down by the strap button and wrap it around one of the bigsby mounting screws under the Bigsby on that bottom edge, or ground one of the bridge posts.

One of these two methods should already be done I would think. If there are other methods, I don't know what they are.....

If the wire has come undone somehow these 2 places would be the first 2 places I'd look. If neither of these methods was used.... well there's only so many wires in a guitar... it shouldn't be too hard to find the ground wire, unless they "forgot" to install it.

 

[LesPauloholic]

Re: Greg

I just removed the Bigsby, and the was no wire present. I can see a wire inside of the f hole that is drilled towards the bridge. Do you think they grounded the bridge that way? All your help is appreciated.

Thanks

Yes.... but check it with an ohm meter to make sure the connection has not failed.

Greg

 

[Mike M]

Well, all of you were correct. The ohms from pot to pot was 0 ohms. From pot to bridge was >9999 ohms, and from bigsby to pot was >9999 ohms. The connection is gone. Now I need to find out if the bridge or Bigsby was connected. I will try to call Gibson tomorrow and ask them. I really dont want to take it to a local repairman. I live in the Atlanta area and don't know who I should trust to do the work. The PAF's solder joints are all untouched, but they look very weak from what I can see. I know as soon as everything is moved around, SNAP!!!! Anymore suggestions would be appreciated. Can't wait to hear the PAF's without that f****** noise. Thanks

 

[Wilko]

Don't worry about the bridge ground. I don't remember my 335 even having one. Your problem is probably more simple. You should get continuity between pots. that's more likely the culprit for a loud enough sound to be that annoying. It's not too difficult to take out the whole harness, solder it up good while out of the guitar and pop it back in place. Make sure there is a wire connecting the chassis of all the pots.You can do this with the pickups still in the guitar. Put a towel over the guitar to keep from scratching it

 

[Mike M]

I made an interesting discovery tonight. After tinkering around with the guitar, I found that the Bridge and Bigsby are not grounded because the ground wire is going to the tailpiece bushings. I removed the CUSTOM MADE plaque near the bridge and discovered the two bushings underneath. I tested the ground on the one that was closest to the controls, and it was properly grounded. No other wires are going into the center wood block. I guess I could find a early sixties tailpiece and get rid of the Bigsby, or drill and solder a new ground wire. Me and soldering iron don't mix. I think the tone and sustain would increase with the tailpeice, but I hate to change anything on an original. Any comments are apppreciated.

 

[Wilko]

I still maintain that a properly wired Gibson will not have much hum, even without the bridge ground. the important ground circuit is all components need to be connected via ground harness, including the jack. That ground circuit goes directly to your amp via your cord. If that doesn't take care of the problem, then consider the bridge ground, keeping in mind that your guitar will still hum unless you are touching the strings (or bridge).

 

[TruelasDougblood]

I made an interesting discovery tonight. After tinkering around with the guitar, I found that the Bridge and Bigsby are not grounded because the ground wire is going to the tailpiece bushings. I removed the CUSTOM MADE plaque near the bridge and discovered the two bushings underneath. I tested the ground on the one that was closest to the controls, and it was properly grounded. No other wires are going into the center wood block. I guess I could find a early sixties tailpiece and get rid of the Bigsby, or drill and solder a new ground wire. Me and soldering iron don't mix. I think the tone and sustain would increase with the tailpeice, but I hate to change anything on an original. Any comments are apppreciated.

Custom Made plaque?? Witholding evidence!! :^)

Back in the 60's Gibson often used those infernal tone sucking plastic/nylon bridge saddles in the tunematics'; if they had grounded the bridge it
wouldn't work so they usually grounded the tailpiece instead. Sounds like they didn't put a
lot of effort into adding the bigsby back in those days either. The trapeze tailpiece ES'd would have already had the ground wire in the proper posistion.

If it were me, and if the humming was so bad that it negated the advantage of having a bigsby, I wouldn't have a problem with putting a stopbar on the guitar, though I wouldn't make the conversion
permanent. Just plop the bigsby in the case and let it go at that. If it were up to me that is...

I had a friend back in high school ( 60's ) that
had pretty much the same 335 and I don't remember it having any humming "issues". Of course it was
30plus years ago, and with all the other stuff humming who could tell :^).

Doug

 

[Wilko]

For the check of teh ground problem, you need to get continuity between all metal components. You should get a reading between all the pots, teh pickup covers and the switch. You mentioned getting "0" between the pots. That is most likely your problem. Check that out.

 

[Mike M]

I agree about the plastic saddles. This guitar has two of them in the center of the bridge. I need to replace those. I thought that the ohms reading betweeen the pots should read 0 ohms. I tested it on my Murphy and that is what the reading showed. The resistance skyrockets whenever contact with the bridge or Bigsby is made. I am going to try the stoptail route for a little bit. No permanent changes. I used a dental mirror to look inside of the guitar for any other ground wires, and found none. Either they forgot or the bigsby was added later. Two other obserations that I made were the letters LP underneath the Bigsby and the bridge pickup cavity with no channel to the electronics. I read in Erlewine's book that a rout was made afer 61 so the controls could br easily accessed. My guitar is a 62 and has no rout. As far as the LP under the Bigsby, I was wondering if that had anything to do with Les Paul.

 

[Wilko]

On using the meter for reading ground continuity. don't use the Resistance measurement, use continuity. It will make a sound or show circuit if there is continuity. You should get a reading between pots on your Murphy as there is a bare wire soldered directly to the backs of all the pots and running to the tailpiece. All the shields (braided wire) are soldered to the same places. making the ground circuit that continues to the amp via your cord. Another common mistake is that the output jack may be wired backwards. Make sure the leads from the caps are not touching anything besides where they are connected.