My humbuckers hum like single coils :-/

[mbratch]

Hey all, I have an Gibson ES347 and the humbuckers are making a moderately high pitched hum that's not stupid-loud but loud enough to be noticeable when not playing and is, I'd say, very much like a single coil hum. The pickups are coil tapped, but I'm getting the noise in full coil mode.

Any idea what might cause this?

Thanks.

[Glass Snuff]

Does the hum go away when you touch the strings?

[mbratch]

Does the hum go away when you touch the strings?

Not at all. Touching any part of the guitar hardware has no impact on the sound. Only turning the guitar volume down causes the noise to go down in proportion.

[FunkyKikuchiyo]

how does the pickup sound otherwise? If it sounds pretty humbuckery then I'm stumped. If it doesn't, then you could have it out of phase with itself (which will cease to cancel hum), or one coil simply isn't coming on correctly and you're always running it in single coil mode.

[mbratch]

how does the pickup sound otherwise? If it sounds pretty humbuckery then I'm stumped. If it doesn't, then you could have it out of phase with itself (which will cease to cancel hum), or one coil simply isn't coming on correctly and you're always running it in single coil mode.

Thanks for asking. It otherwise actually sounds great. The coil tap switch does what it's supposed to: nice and fat when off, and thinner when on, for both pickups.

I don't think it's always been this way. Not very long ago I did take the whole thing apart and add bright caps (cap+resistor) to the volume controls using values recommended by the pickup manufacturer. The guitar is an ES347 so it's a monster to operate on, but I carefully went through it all. I can't swear to it, but it's possible the noise appeared after that operation and I may not have paid much attention the first time.

[FunkyKikuchiyo]

I'd go over the touch test again to see if touching anything impacts the noise. if it is RF or grounding problems, you'll eventually find something that changes.

Also, check continuity of the grounds (shield of the cable) to the hardware, I don't remember exactly where that runs on this guitar.... often to the tailpiece on Gibsons, though. Sometimes to studs for the bridge, but that is less common. If it is strung up it should be on all strings, anyway. If you pulled that free in the gutting process and didn't reattach it, then you aren't grounding properly.

[mbratch]

Thanks. I'll check the grounding. If I recall, there's a ground wire running to the bridge stud. This is a 1981 model. I know I touched every piece of hardware with no change, but I'll double check that.

[David Schwab]

Those are the covered Dirty Fingers pickups. I had a set from a ES-347. The owner wanted something cleaner sounding.

They were a little on the noisy side. I liked the tone, but ended up selling them because of the slight hum. It would get worse with distortion.

I'm not sure why they hum, but I couldn't do anything to stop it.


ES347

[mbratch]

Those are the covered Dirty Fingers pickups. I had a set from a ES-347. The owner wanted something cleaner sounding.

They were a little on the noisy side. I liked the tone, but ended up selling them because of the slight hum. It would get worse with distortion.

I'm not sure why they hum, but I couldn't do anything to stop it.

ES347

Thanks for the reply. Actually they aren't the Dirty Fingers. I replaced the stock pickups several years ago with Harmonic Design Vintage humbuckers. They didn't used to hum like this and I'm trying to figure out why.