Noisy Jazzmaster

[mynameisjonas]

but... if the pickguard already has an aluminum shield, will foil make any difference?

[parry]

So lining the cavities with aluminium foil will do the job? I thought it had to be the special stuff... Nice!

I'll try and find my resources (it's been a while) - but I remember when I was digging around, I read that thickness had something to do with the sheilding properties, and that household aluminum foil wasn't quite thick enough...

But yeah... I too am wondering how much affect it'll have, if you already have the aluminum sheild in place...
Could it just be a simple grounding issue? Like, a wire jiggling loose?

[mynameisjonas]

I'll try and find my resources (it's been a while) - but I remember when I was digging around, I read that thickness had something to do with the sheilding properties, and that household aluminum foil wasn't quite thick enough...

yeah i remember that too. something about a certain thickness actually increasing RF interference...

[parry]

Jyep! Some digging around on Faraday Cages should net results...

[parry]

Hmmmmmmm...
I was poking about - looking at other stuff - when I stumbled upon something that might be worth checking out...

Before you hunker down and rip the JM apart... haven't you gone through a gear adjustment with pedals and junk lately?
Have you tried plugging the JM straight in to your amp to see if it's the same amount of noise?
Maybe the noise is coming from your power supply, or signal chain...
Maybe?

EDIT: sorry if that's a "well, DUH! YEAH!" thing... I just know I do stuff like that all the time...

[StevenO]

Yeah, I've tried all of the obvious things. I'm thinking it has a lot to do with a grounding problem at my house, but it might be more than that.

There's definitely no issues with "when I touch a screw, the noise goes away". So it's not a grounding issue in that regard...

Over the weekend I did some recording at the bass player's house (he composes for TV, radio, etc, etc.) and there was zero noise from my set up. I, with my guitar, was in a separate room from my head and cab, though, if that makes a difference.

Just seems really annoying when we have practice and from my end it's just a ridiculous amount of noise. I'm going to chop it up to a grounding issue in my house anyhow.

I'll take apart my guitar today and check out the grounds, and maybe even resolder them if need be.

[johnnygrand]

I run lots of high gain pedals and have run across the same issues with mine. I fixed my noise problem with a MXR Smart Gate, a really cool gate that doesn't screw up picking dynamics or pinch off sustain. You can grab them used for under $70.

[Orang Goreng]

I think no matter how well you shield the wiring in the guitar, you still have the problem of the unshielded coils of the PUs. They're big antennae, and I'd imagine they pick up way more crap than those relatively short stretches of relatively thick wire connecting everything. Perhaps find a way to shield the PU covers? I've tried this in the past, pretty much with the method Curtis just described (I'd imagine shielding paint works just as well), but I could never get a stable ground path from the foil to the rest of the shielding. I can imagine that should easily be doable with a piece of bent copper inside the cover, though. Solder that with a wire to the body shielding, and you may have a stable Faraday cage around your PUs.
I (was forced to) split the neck humbucker in my SG recently, and was surprised to find that it's completely quiet, even though it's now a single coil. The only reason I can think of why that is, is the metal humbucker casing it is still sitting in.

[fullerplast]

It only happens at your house?

Are there florescent lights in the room? I've heard something about 60 cycle/60 Hz interference causing hum and buzz, and thats what the old tube lights operate on...

[sewkid]

Have you tried moving your equipment to a different room and plug everything into a different circuit? Could it be incorrect wiring in your house?

[sambooka]

I just bought a traynor YGM-4 so I am playing my JM a bit more than usual. The hum in my house is abysmal and I have some thoughts/observations that need straightened out.
My JM is CIJ. Aluminum foil on the PG and painted body cavity. Just for shits and giggles I also shielded/grounded the pickup covers and replaced all the wiring with gibson style shielded cable. I dont use the lead circuit so I disconnected it. Pickups to the toggle, toggle to the pots, pots to the output jack. I even put the tone cap on the o'scope to find out which lead was the outer foil and put that lead to ground(which doesnt make a damn bit of difference to my ear but did it anyway). Checked continuity and everything is grounded as it should be. My cables are little old but still seem ok. Good quality belden/switchcraft from about 15 yrs ago (yeah yeah.. when I get around to it)

1) My house was made in 1926. Old wiring mixed with new from the 80s. All copper but not all outlets are grounded. The ones I use for amps are tho.

2) My house also has a stupid number of dimmer switches from the 80s (it was the 80s.. seemed like a good idea at the time I guess). I havent replaced them. I have heard that they tend to add RF or 60Hz noise. Not sure which. Anyone have any experience?

3)With the volume rolled off on my guitar the amp is quite quiet. Any noise is coming from somewhere between the pickups and the first preamp stage of the amp.

4)When I touch the strings on my guitar there is no change in hum. My understanding is that this is because I have already shielded the bejezus out of it. My body, as massive as it is, doesnt provide any additional shielding. So that leads me to 5....

5)When both pickups are engaged (RWRP) all the noise is GONE (well enough to make the situation livable). So here is my take on this.. please correct me. If both pickups together buck 99% of the hum then 99% of the hum MUST be coming from the pickups. Noise injected because of poor shielding in the control cavity wouldnt be cancelled out by engaging a second (rwrp) pickup.

So unless someone can (and please do) shoot holes in this i have to conclude a good little test is this : If your guitar is quiet enough when both pickups are on (again assuming RWRP), then shielding isnt really your issue. Single coils are noisy. Because of the larger surface area of the coil JM pickups are REALLY noisy.

Sorry for the long post. I know some of it is irrelevant. Didnt want to leave anything out.

[StevenO]

Yeah, I've been thinking that it's just the pickups, which makes sense. I just don't understand how some people's Jazzmasters are almost noiseless. Or how some can use compressors with their Jazzmasters... Seems crazy to me. The noise is almost overpowering for me in my practice room, but all is at it should be inside my guitar - everything is shielded and grounded.

Oh well. I guess I'll just have to live with it.

[Orang Goreng]

Have you tried your set-up in other places? Your practise room may have some anomaly with its mains power. There's a club in Amsterdam next to the railway tracks where they has to install some filter on the power supply because otherwise they essentially cannot have guitarists with single-coil guitars on stage (they even request in their stage info that, if possible, guitarists bring a humbucker model, as the filter reduces, but not eliminates the problem). It may just be that room?

I take it that the problem is gone or much reduced when you switch both PUs on?

[bubbles]

I think no matter how well you shield the wiring in the guitar, you still have the problem of the unshielded coils of the PUs. They're big antennae, and I'd imagine they pick up way more crap than those relatively short stretches of relatively thick wire connecting everything. Perhaps find a way to shield the PU covers? I've tried this in the past, pretty much with the method Curtis just described (I'd imagine shielding paint works just as well), but I could never get a stable ground path from the foil to the rest of the shielding. I can imagine that should easily be doable with a piece of bent copper inside the cover, though. Solder that with a wire to the body shielding, and you may have a stable Faraday cage around your PUs.

I did just this, but instead of bent copper I used excess copper tape on the inside near the pickups, and lined the covers with the tape as well, then used a multimeter to test for continuity....and made sure that everything was grounded before placing it back in the guitar. It did help, but I am not sure it was worth the trouble.

I usually use the rhythm circuit the most on my Jazzmaster, and the lead circuit usually gets the volume turned all the way down, so I just flip the lead/rhythm switch in between songs and if not just dial down the volume knob. Its very cheap, very effective, and I love rolling up the hum right before crashing into a song intro. Sometimes the easiest solution is the best. The guitar is made with a volume knob. It works amazingly well!