For Muscians: Les Paul PAF Humbuckers Hum 60 Hz

Grounding is good.

My brother-in-law has a Tube & Solidstate hybrid amp for his audio system that he has a separate ground for. It is truly an awesome sound system.

(He's got the sound system grounded with its own spike out in the yard.)

The entire thing is exposed without a cabinet in the living room. Big ass tubes. They help heat the room.

Those guys that recorded Steely Dan, really knew what they were doing. To this day hardly any have ever surpassed their skill at recording.

Apparently Stevie Wonder recorded on videotape. I had the opportunity once to shoot some Jazz video footage in a Bowery Sound Studio he had recorded in.

The DAT,and the Sony Mini Disc are terrific recording machines in my opinion.

Yes no hum with strings issue and 2 amps and 2 cords same thing. A music store professional checked it out. I have a Gibson Les Paul wiring diagram and looked at the pickups briefly they are cheap and saw (1) coax cable should be (2) wires for each pickup and shielding not to impressed so what you are saying I am going to check it out. Only hums bad at high Guitar volume also. That is the pickups or from the pickups. I have seen PAFs for $20 dollars a piece Bouquete wiring USA made on eBay. Tone is great!

"Yes no hum with strings issue"

Do you mean that it stops humming when you touch the strings?

If so, your chassis is not properly grounding to your ground wire in your cable, which is grounding the amp and guitar together. You need to make sure all the metal on the guitar is grounded (basically). your bridge should have a wire or some conductor of some kind attaching the bridge to the rest of the common ground. The strings are becoming grounded to you when you touch them, thus eliminating the buzz. When you are not touching the strings, they are floating without a ground, acting like magnifiers of any small frequency, IE 60Hz background hum.

So in the end, you have a missing/bad ground/s. Properly ground EVERYTHING, and your hum will disappear.

Good luck, and keep us posted.

Thanks I meant that the strings have nothing to due with the hum. The volume controls do when you turn them up more hum which is either the pickups are not wired out of phase, lousy grounding, or volume control pots. The hum by the way is not that noticeable except to me. Thanks for your help.

Thank you for the great informaton.

I just bought a Chinese made Epi Les Paul Black Beauty with the 3 pickups. I absolutely love it, except for the hum at higher gain levels. I did a Google search for epiphone les paul humm and it led me to your comments. Exactly as you say, the hum is most pronounced when I am not touching the strings, then goes almost silent when I touch them. The amp I am using is a Marshall MG100HDFX head and 4X12 cabinet. Other guitars do not hum when using same amp and cord.

My initial investigation showed little shielding inside the les paul, although when checking pictures of the insides of other Epi Les Pauls, they did not have much shielding either. The grounding looked OK inside, but I did not really check it other than a brief look. I did not even think to check the bridge. I will check all grounds thoroughly now, as well as the bridge. I will probably also add some shielding, since I have some extra foil tape that I might as well use.

Any other suggestions? I will do as you indicated and post the results of my work, although it may take me a week to get it done given my work schedule.

But I especially wanted to thank you again for addressing this issue.

jjlewis

San Francisco

Look for cold solder joints made with "lead free solder". resolder all connections with good 60/40 electronic rosin core solder. the lead free solder doesn't wet as well, requires more heat (and therefore gives more cold solder joints) and will eventually grow tin whiskers and short stuff out.

switching to lead free solder was the stupidest thing anyone ever did.

Agreed. When I open up a project and see possible lead free solder joints, I pull out the iron, sucker, and spool, and go at re-soldering all of them. The most frustrating thing is trying to find an open, with all good "looking" solder joints, only to find that 4 hours into the diagnosis, it was a poor joint to begin with.

Yep! I'm starting to hoard 60/40 Rosin Core, as I fear it may well become unavailable. I've been using lead-based solder for over 60 years, commonly holding it in my mouth, with no observable effects.

You wrote:-

"commonly holding it in my mouth, with no observable effects."

How can you be so blind? WE ALL NOTICE THE EFFECTS IN ALL YOUR POST!! IT AIN'T PRETTY!!!

Haven't you noticed that you are too heavy to float in water anymore?

But please "Solder on" as before........

Hum is often produced not directly by grounding, but grounding in a loop. There is a reasonable explanation of the effect and how it happens here!

This can mean that you need to separate all the grounds in the guitar, make a ground point from the connecting cable and link each unit within the guitar only once to that point and that point only....fiddly!

The strings.

I am going into unknown territory for me here!! I have never done anything like this, but here goes anyway:-

Are they grounded or linked to each other? Use an Ohmmeter to test, less than 1 Mohm should be considered as being a link as a starting point. Sweat could produce that so keep things clean and polished.

If not linked, can you add a piece of metal, brass or similar on the main bridge and connect this to the central earthing point in the guitar previously mentioned.....many Guitars have a metal bracket that all strings are connected to at the Guitar end, take a wire from that bracket in some way, test that the connection to all conductive strings is less than 1 Ohm....less is better.

Make sure that they are not linked at both ends of the strings, that would be catastophal......if you also have a metal bridge (its called the Nut I am told) at the other end of the fret = disaster....ground loops......4, 6 or 12 of them!! replace it in some way, or insulate all metal strings from the bracket (called a Bridge still in the Wiki article) in some way......but then you need to run a wire from the end of the fret to the central earthing point.....maybe via the strap..?

I found this interesting Guitar link here!

Experiment to see what helps with flying leads, then only build in the "good" fixes.....

I hope this all helps.

A link that I forgiot to add is:-

http://www.rane.com/note110.html

Its an "Oldie but Goody" on the subject of ground loops.

By the way RV I have the vintage wiring diagram of Les Paul electronics if you are interested. I can email a pdf attachment. I bet these pickups are made in China then I will buy the (2) pickups I saw on eBay after I check all wiring. The pickup wires are two small should be 4 wire. Shields from pickups are prime suspect.

Ahhh... good to clarify. Well, then a chassis ground problem is not likely. But I'd still check to make sure all the pot's are tied together well on their body's, and check they they are also hooked to the common ground. If indeed they are, you might think about those PU's.

Also... have you checked for hum in other rooms/places with different lighting/electrical sources? I have played in some places with poor electrical grid, and crazy lighting, which causes all kinds of havoc on the equipment. I have noticed a particular problem while playing in places with a lot of "Christmas" lighting strung about. My Bass player's bass has active PU's, and it is particularly susceptible to lighting buzz/hum. He can face one direction, and no buzz, but If he turned to look at the drummer, his bass would barf.

RV I had an active bass Ibanez (2) of them they had good pickups but the type of noise if not Sinusoidal may interfere. I have tried (2) of everything location, amp, and cords but not pickups but I will still clean up the wiring. I have seen good pickups with shield around the wires as well mine just plastic probably wired inside pickup for joining the two humbuckers to be out of phase then bringing out a single coax to the pickup selector then volume pots. Access plates are Not grounded either from the inside.

Hum is almost invariably due to a ground loop. you've got one or more components that due to a bad connection is at a higher ground potential than the rest of the components of the circuit. go back throughand make sure everything has a good solid low resistance electrical ground and I'd be willing to bet you'll solve the problem.

Thank-you I was thinking the exact thing as well as shortening wiring, improved grounding, check the caps to see if they are Gibson standard and the vintage Gibson wiring guide I have. Last check the pickups and their wiring and shielding and see if they are USA made. Scan the electronics with a degausser to pinpoint areas on bad shielding or bad pickups. I may add shielding over critical wiring and ground one end of the shield at the pots to avoid ground loops.

I'm with you on this, not that I am an expert on grounding, but I have found and fixed a few ground loops in my time on both audio and computer equipment.

Grounding needs to be central, all equipment going back to one point. This point then going to the house/mains ground.

I have even found new stereo equipment that caused hum when plugged in because it was built wrongly....

By the way, is the hum there with or without your guitar? It is possible that the guitar can cause the problems....even though on another amp its fine.....

If it is the Guitar and you don't want to fix it/its not easy to fix, use a radio link to fix the problem.....

It is the Guitar on two amps and two cords and two locations my Guitar tech checked it out after setting it up and said I think it is the cheap PAF pickups probably Chinese. I have my eye on a couple of USA made PAFs or I could go Seymour Duncan. I have one of these on an acoustic and no hum at all. Pickups are coils and they love magnetic signal and if they are not wired right or a bad brand they will hum 60/120 Hz.

I just replaced a friends pickups. He had a Fender Performer, with stock pickups, which sounded ok, but not screaming for blues. He bought some Seymour Duncan's which I think were aimed for Jazz... They definitely were screamers, and man he could wail on some blues solo's with the new pickups. I definitely recommend Seymour Duncan when considering pickups. However, their "wiring diagram" was incorrect, and when wired according to the literature on their website, the pickups would not work correctly. I wired them as standard pickups, with dual push/pull pots, and everything works great.

For some reason I constantly have a giant pile of broken equipment... every time I finish with one project, someone ends up on my porch with some other broken piece of band/audio equipment, or something they want to mod. it's a fun hobby, as long as it remains just a hobby. Right now, I have 2 mixers, 3 solid state amps, 2 tube amps, 1 guitar, a PA speaker crossover, and a combo amp/cab PA setup to work on, which seems to be about average. Maybe I should start charging for more than parts.

My Telecaster has single-coil pickups and atrocious 60 Hz hum, wish there was something to be done about it. Maybe someone here a whole lot smarter than me knows - care to share? BTW, grounding & connections are good so far as I know

Teles are famous for there "single coil" pickups which are not designed to cancel out noise. They are made that way for tone and to be hot for overdriving your amp. I have a Strat that has 2 singles and a bridge humbucker. This helps when you are in switch positions 4 and 5. 5 being only the humbucker. This is a way to cut down on noise during a lead solo which is typically higher gain. The best thing to due is use a noise gate which cuts out the hum when you are not playing. When you start to play S/N wins no hum just the guitar is heard. It also is interesting to note that a noise gate used by bassists cuts down on string noise as well. The best noise gate I have ever used is made by DBX. There are stomp petals but I like the LED display on the half rack DBX that gives you feedback on the signal being gated out. I have seen single coils that say they are quiet but there is no electronic evidence to back this up. A noise gate will solve most of your problem.

I'm surprised that after 11 responses, no one has mentioned power supply capacitors. Old capacitors commonly leak out their electrolyte, and loose their capacity to filter DC.

If the device is old enough to use tube or selenium rectifiers, they could also be contributing to the problem.

Your half right at the beginning of your reply. It sounds like your talking about a vintage amp that needs a recap job and you are absolutely correct. We are talking about a Les Paul Guitar new with coupling caps 0.022uf and Hum 60Hz pickup from a ground loop or a bad connection or just cheap Guitar pickups. Humbuckers are two coils out of phase that should cancel Sinusoidal noise that is common mode to both pickups.

Hello,

Have a look here : http://www.guitarnuts.com/index.php

And don't play just in front at 50cm from your amp, but go sit down a few meters away to prevent the amps' feeder transfo magnetic coupling with the windings of your PU.

Ciaou,

Laurens

Trot your browser to Stewart Macdonald.com They have a wealth of tech info there on guitars. Yhey sell parts, books on repair etc. They give good service and are sure to have some reference info you will find useful.

This details correcting a noise problem on a Fender Jazz bass and may apply to your situation as well.

http://www.talkbass.com/wiki/index.php/Silencing_the_Noise_on_a_Marcus_Miller_Signature_Bass

I'd only put money in it to make it sound good if if plays (feels) good too.

http://www.guitarcenter.com

http://www.musiciansfriend.com