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  • #16
    You say some humbucker guitars are noisier than others.
    Curious which ones are the worst?
    If they are the LP type, how the 3 way switch is wired, can make them noisy.
    I've rewired a lot of LP imports to get rid of that noise.
    T
    "If Hitler invaded Hell, I would make at least a favourable reference of the Devil in the House of Commons." Winston Churchill
    Terry

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    • #17
      Originally posted by big_teee View Post
      You say some humbucker guitars are noisier than others.
      Curious which ones are the worst?
      If they are the LP type, how the 3 way switch is wired, can make them noisy.
      I've rewired a lot of LP imports to get rid of that noise.
      T
      That wouldn't have changed in the last 5 months I wouldn't think, provided the guitars did not get worked on.
      nosaj
      soldering stuff that's broken, breaking stuff that works, Yeah!

      Comment


      • #18
        Originally posted by nosaj View Post
        That wouldn't have changed in the last 5 months I wouldn't think, provided the guitars did not get worked on.
        nosaj
        He says some are louder than others.
        I was addressing that.
        "If Hitler invaded Hell, I would make at least a favourable reference of the Devil in the House of Commons." Winston Churchill
        Terry

        Comment


        • #19
          Originally posted by big_teee View Post
          He says some are louder than others.
          I was addressing that.
          Makes sense.
          Anyone concur with the light being a good possibility?

          nosaj
          soldering stuff that's broken, breaking stuff that works, Yeah!

          Comment


          • #20
            Originally posted by Chuck H View Post
            The reason some of your guitars hum more/less than others is likely a combination of specific properties. Some guitars are shielded better than others. Some conductive paints are better than others. Some humbuckers have more symmetrical coils and will cancel hum better. The higher a pickups output the more it can transfer any noise it picks up. So...

            Let's say you have a guitar with less than great shielding and a high-ish output humbucker that has a small offset in the coil windings. At face value it looks to be appointed similar to another of your guitars. But that one may have more ideal shielding and somewhat lower output pickups with symmetrical coils. The former will hum more than the latter.
            To expand upon your reply, there is 60hz hum which a humbucking pickup addresses. As you said some hbs do that better than others.
            And there is a higher pitched "hash" static-y noise that is addressed by shielding the control and pickup cavities in a guitar. Often called RFI it can be transmitted through house wiring. Some solutions work better than others with this non--hum noise.

            Conductive paint can work well but it usually requires several coats with several hours if not more between the coats. And once you open the can and let air in it might not still be usable a few years later...

            I prefer to use the copper foil tape that you can order from Stew Mac or Amazon with the conductive adhesive (very important!) You will have to remove the pots, etc., to do it right but there is no waiting time between coats. You will want to glue heavy duty aluminum foil on cavity covers and run a narrow strip of foil tape to one or more screw holes to insure a positive connection. I always solder the seams of adjacent strips just in case the adhesive lets go later and you need a good connection between the copper foil tape and the ground wiring in the guitar (either solder or a lug.) BTW that is also very important when using conductive paint — do not assume that the pots and bushings will be sufficient (the guitar mfgs never do.)

            FWIW the imported guitars these days are more likely to come from the factory with shielding (always conductive paint) because their assembly process can allow for proper drying and recoat times. Gibson guitars usually come with no shielding at all these days although the LP Standard I bought in 1976 $600 had a metal plate under the pots and a metal cover that went on top of it.

            Back to you, Chuck.

            Steve A.
            Last edited by Steve A.; 07-14-2018, 09:53 PM.
            The Blue Guitar
            www.blueguitar.org
            Some recordings:
            https://soundcloud.com/sssteeve/sets...e-blue-guitar/
            .

            Comment


            • #21
              Originally posted by nosaj View Post
              Makes sense.
              Anyone concur with the light being a good possibility?

              nosaj
              Yes, but it can be switched off to test that as was suggested earlier, right? Did anyone already mention light dimmers? Also is this a single family home or are there multiple units in which a neighbor might be doing something differently? Is there perhaps an electric company transformer within X yards of the house? I live in a 4 unit condo with a utility transformer across the street so I must deal with all sorts of noise..

              Steve A.
              The Blue Guitar
              www.blueguitar.org
              Some recordings:
              https://soundcloud.com/sssteeve/sets...e-blue-guitar/
              .

              Comment


              • #22
                Originally posted by Enzo View Post
                What we do is track down the source of the problem. That tends to make clear the WHY of things.
                That’s a good one, Enzo. Thats an important part of succesful troubleshooting, And I don’t know if I’ve heard it said any better.
                If I have a 50% chance of guessing the right answer, I guess wrong 80% of the time.

                Comment


                • #23
                  Originally posted by Steve A. View Post
                  Back to you, Chuck.
                  Thanks Steve! This just in...

                  Good points on shielding and info on modern Gibson practices. I didn't know they weren't shielding all their guitars.

                  The humbucker design works on any noise picked up by the coils at a frequency covered by the spacial relationship between the coils. So, pretty high above strictly 60Hz. I've used this to my advantage in designing "other" stuff too. And obviously anything in the HF like static and RF are just too tiny for the humbucker coils to effectively "see" the same thing on bioth coils. Ergo, no cancellation.

                  You can buy brushable conductive paint that is water based. I know this because I painted a house with it once. Very expensive as house paint goes at something like $649.00 (retail) for a five gallon bucket. But you could paint A LOT of guitar cavities with five gallons. Probably about 649 This was a coating made specifically to block cell phone tower signals. This customer had recently had a cell tower go up in line of sight with their home and they were wearing tin foil hats and taking readings with an EMF meter when I arrived (they weren't really wearing tin foil). Anyway... I painted the house with the coating, which looked really boss actually since I'd never painted a house BLACK before, and then I painted it with a more pedestrian color scheme in regular house paint. Before I put the house paint on I couldn't resist punching my meter probes into the coating to see how conductive it was. Keep in mind that this was a water based binder. With a typical "rolled on" coat thickness and my arms spread as far apart as I could, the highest resistance reading I could get was 27 ohms. That's with almost six feet between the probes. I thought that was pretty damned good. After I grounded the film (with the supplied kit and according to instructions) The customers EMF meter was pretty much tanked at virtually no reading. Mission accomplished and my customers will be money ahead in about a hundred years because they didn't have to buy all that extra tin foil.

                  I saved some of the coating to experiment with but I haven't had a project for it yet.
                  "Take two placebos, works twice as well." Enzo

                  "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                  "If you're not interested in opinions and the experience of others, why even start a thread?
                  You can't just expect consent." Helmholtz

                  Comment


                  • #24
                    Originally posted by Chuck H View Post
                    Thanks Steve! This just in...

                    Good points on shielding and info on modern Gibson practices. I didn't know they weren't shielding all their guitars.

                    The humbucker design works on any noise picked up by the coils at a frequency covered by the spacial relationship between the coils. So, pretty high above strictly 60Hz...

                    You can buy brushable conductive paint that is water based. I know this because I painted a house with it once. Very expensive as house paint goes at something like $649.00 (retail) for a five gallon bucket...

                    Before I put the house paint on I couldn't resist punching my meter probes into the coating to see how conductive it was. Keep in mind that this was a water based binder. With a typical "rolled on" coat thickness and my arms spread as far apart as I could, the highest resistance reading I could get was 27 ohms. That's with almost six feet between the probes. I thought that was pretty damned good....

                    I saved some of the coating to experiment with but I haven't had a project for it yet.
                    I keep a can of the water-based StewMac conductive paint around and use it where the copper foil tape might be overkill. I ohm it out with test probes and it seems to work best with 3 properly timed coats. One concern (possibly unfounded) is that a thin single layer might flake off and get inside the pots. Especially if the paint in the can had dried out a bit after a few years. With one guitar I put a clear coat of something over the conductive paint just to be sure.

                    Here's a real life horror story... In the early 80's I rewired my 1976 LP with Schector P-P OmniPots using the drawing in the Brosnac book for the Jimmy Page wiring scheme. I had to remove the metal base plate and cut into the wood a bit for the neck volume pot so I used an MEK-based conductive paint from Stars Guitars in SF to shield the control cavity. "Be sure to mask off the holes for the pots to protect the finish."

                    I had no masking tape around so I figured that Scotch Magic Invisible tape should work just as well, right? Everything looked fine until I removed the tape and found the nitro finish mottled around all 4 pot holes... Argh!

                    Steve A.

                    P.S. I mentioned soldering the seams between the strips of copper foil tape... I usually get out my 60-40 plumbing solder and coat the entire foil surface with it. "To keep Superman from using his xray vision to reverse-engineer my custom wiring harness!" if anybody asked. (Before I learned about StewMac I'd buy the 4×10" sheets of copper foil tape from GC at the local electronics parts house which did not use a conductive adhesive so you had to run a solder bead between adjacent sheets.)
                    Last edited by Steve A.; 07-14-2018, 11:34 PM.
                    The Blue Guitar
                    www.blueguitar.org
                    Some recordings:
                    https://soundcloud.com/sssteeve/sets...e-blue-guitar/
                    .

                    Comment


                    • #25
                      Originally posted by Steve A. View Post
                      To keep Superman from using his xray vision to reverse-engineer my custom wiring harness!
                      Hardy LOL

                      That thieving sell out is working for The Man. You know it.
                      "Take two placebos, works twice as well." Enzo

                      "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                      "If you're not interested in opinions and the experience of others, why even start a thread?
                      You can't just expect consent." Helmholtz

                      Comment


                      • #26
                        Originally posted by Steve A. View Post
                        I keep a can of the water-based StewMac conductive paint around and use it where the copper foil tape might be overkill. I ohm it out with test probes and it seems to work best with 3 properly timed coats. One concern (possibly unfounded) is that a thin single layer might flake off and get inside the pots. Especially if the paint in the can had dried out a bit after a few years. With one guitar I put a clear coat of something over the conductive paint just to be sure.

                        Here's a real life horror story... In the early 80's I rewired my 1976 LP with Schector P-P OmniPots using the drawing in the Brosnac book for the Jimmy Page wiring scheme. I had to remove the metal base plate and cut into the wood a bit for the neck volume pot so I used an MEK-based conductive paint from Stars Guitars in SF to shield the control cavity. "Be sure to mask off the holes for the pots to protect the finish."

                        I had no masking tape around so I figured that Scotch Magic Invisible tape should work just as well, right? Everything looked fine until I removed the tape and found the nitro finish mottled around all 4 pot holes... Argh!

                        Steve A.

                        P.S. I mentioned soldering the seams between the strips of copper foil tape... I usually get out my 60-40 plumbing solder and coat the entire foil surface with it. "To keep Superman from using his xray vision to reverse-engineer my custom wiring harness!" if anybody asked. (Before I learned about StewMac I'd buy the 4×10" sheets of copper foil tape from GC at the local electronics parts house which did not use a conductive adhesive so you had to run a solder bead between adjacent sheets.)
                        Stain Glass shops sell it reasonably also.

                        nosaj
                        soldering stuff that's broken, breaking stuff that works, Yeah!

                        Comment


                        • #27
                          Originally posted by nosaj View Post
                          Stain Glass shops sell it reasonably also.

                          nosaj
                          Oh, you're going back to the brick and mortar era (don't we all wish) I use to buy the stuff at stained glass shops when they still existed. In that case you can't be sure of the conductivity of the adhesive so you need to be sure and put a solder blob at any seam.
                          "Take two placebos, works twice as well." Enzo

                          "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                          "If you're not interested in opinions and the experience of others, why even start a thread?
                          You can't just expect consent." Helmholtz

                          Comment


                          • #28
                            Originally posted by Chuck H View Post
                            Oh, you're going back to the brick and mortar era (don't we all wish) I use to buy the stuff at stained glass shops when they still existed. In that case you can't be sure of the conductivity of the adhesive so you need to be sure and put a solder blob at any seam.
                            Well when you live on an Island....
                            We have some here in Pensacola. Gotta have something for the retired folks to do around here.

                            nosaj
                            soldering stuff that's broken, breaking stuff that works, Yeah!

                            Comment


                            • #29
                              Good eye. i built the heathkit guitar amp the 1st year it came out,1960.
                              Str8 into clean side of amp has little hum. Overdrive side has LOTS!
                              The AX3000g has a noise suppressor built in.
                              All was fine until about 5 months ago.
                              No changes to guitars or rigs, just started to have hum issues on all rigs
                              with certain rigs. I changed the 3 way switch on my les paul ( duncan sh1 59's ).
                              No change
                              Strange that 2 of my hi-output guitars have little to no hum
                              Strat made by my tech ( sharpen-your-axxe ) EVH with steve vai evolution pickup
                              and my Eastwood Ovation Ultra GP ( 14k pickups ).
                              Enzo's use of the humming guitar to follow to the source is what I will do
                              when my electrician gets here to help me
                              Thanks all
                              Clay

                              Comment


                              • #30
                                Originally posted by Gunn_Slinger View Post
                                Good eye. i built the heathkit guitar amp the 1st year it came out,1960.
                                Str8 into clean side of amp has little hum. Overdrive side has LOTS!
                                The AX3000g has a noise suppressor built in.
                                All was fine until about 5 months ago.
                                No changes to guitars or rigs, just started to have hum issues on all rigs
                                with certain rigs. I changed the 3 way switch on my les paul ( duncan sh1 59's ).
                                No change
                                Strange that 2 of my hi-output guitars have little to no hum
                                Strat made by my tech ( sharpen-your-axxe ) EVH with steve vai evolution pickup
                                and my Eastwood Ovation Ultra GP ( 14k pickups ).
                                Enzo's use of the humming guitar to follow to the source is what I will do
                                when my electrician gets here to help me
                                Thanks all
                                Clay
                                Setup to play and then turn off that flourescent light, does the hum go away?

                                nosaj
                                soldering stuff that's broken, breaking stuff that works, Yeah!

                                Comment

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