hi all im a newbie and hope someone can help.
i came into the posession of a guitar that had no pups and no wiring. i have wired up guitars loads of times before and im very handy with a soldering iron. right this one was no different appart from i cant get rid of an earthing problem. you know the scenario, touch anything metal and it goes away. i know i have grounded everything,the pick ups,bridge all pots, jack socket etc all in a loop. ok, it got me so frustrated i thought i might have a dodgy jack socket or pot etc, so i replace all hardware and resolder everything but still got the problem. ok so now i shield the whole cavity then soldered the copper foil to ground. still there... grrrrrrrr, ok i thought it might be the pickups, so de-soldered one at a time, still there, desoldered both and still there. the diagram i followed is from seymour duncans website and know obviously its right. i have checked my wiring against it and all is correct, trust me, gone over it more times than i ever studied at school,not only that ,everything works as it should appart from this annoying buzz. my guitar leads and amp are all fine as i use them on other guitars without this problem...any ideas appart from the obvious in what else can cause this?
Are the pickups internally shielded/grounded? If not, you could put some copper shielding tape under the pickup so the magnet touches the tape, then solder a wire onto the shielding tape and ground that.
First of all, are you certain this is not simply a very (electrically) noisy environment? No problems with other guitars?
The only other comment I can make is based on the description of your grounding/earthing "in a loop." A loop is NOT a good topology for ground (or power, if it every comes up) connections for noise immunity. STAR wiring is preferred. This means choose ONE point on your guitar - back of a volume pot is common, and assign that point to "Ground." Then wire all other parts of your guitar in need of ground directly to that point and that point only. Do not interconnect the grounds of any of your pups, bridge, cavity shield directly to each other, but make sure they are connected to each other ONLY through that single ground point. The reason is a star ground topology has no "loop" that will support magnetically induced current flows (e.g., from bridge to a pup via the common ground and then pup to bridge via a second connection).
Will this fix your problem? I'm not sure. But if you are in an area that has high magnetic field interference (currents through house wiring, power supply transformers in amplifiers, appliance wall worts ...), then loop topology ground is more vulnerable to these sources of interference.
-=tension & release=-
thanks for the 2 above posts, ill try the suggestions today, ill let u know how i get on...cheers j
I built a very noisy lap steel. used Seymour Duncan pickups and the wiring diagram. and yes, they are accurate.
it could not lose the noise until someone told me to run a wire from each pot to earth.
worked great. no unwanted noise.
I read in your post that your grounded the pots. hmmmm. I think gnease is on to something.
well well well well, blinking found the problem. ha ha ha who would have thought it. after initially wiring the guitar up, when i restrung the guitar and played it, the "e"string snapped straight away.(old strings)..... anway, looking at your above comments i decided to try XylemBassGuitar suggestion first, as when i used the term(loop) sorry about that, what i meant by that is all the wiring was a complete ciruit.
anyway, i removed the bridge pickup to apply some shielding and i find caught underneath, the ball gold end of the snapped string i broke with little string attatched to it which was resting on the pickup. removed and threw it away lol and buzz has gone....you couldnt make it up lol grrrrrrrrrrrr wasted lots of time here ha ha, thanks all for advice....j
just a final note, if your wondering how the ball end could have got into the pickup cavity, then this guitar had open pickups (no surrounds) and the bridge is a wraparound style. so if the string snaps at the bridge end, then its only a couple of cm's away from the pickup route :D i doubt anyone will find this thread usefull but might serve merely as a laugh lol.
good to hear you found the issue. lesson? unexpected, weird stuff happens.
-=tension & release=-
Glad you fixed the problem stonester!
Noise problems with wiring are always hard to answer without seeing the instrument becuase there are soooo many factors that can cause the noise. That's definitely the first time I've heard of something like this happening.
