Single coil noise????

[newpatch]

Hi,

I finished wiring my new project. SD Quarter Pound in the neck, SD Distortion in the bridge. The bridge pickup is wisper quiet, but when I switch to the single coil I have hum. If I'm 6 ft away from the amp (DSL50) is quiet, but when I'm by the amp or in front I have the hum...It actually squeels when I face the amp.

I have copper shielding in all the cavities, and all the electronics are new....

Any idea's?

dinkyguitar

 

[Jusatele]

first, check all your grounds and the entire ground path, then look at the ground solder joints to see if they are good
then report back

 

[line6man]

That sounds like a textbook case of single coil hum.

Single coil hum varies with your proximity to a source of magnetic field noise, such as transformers, CRT monitors, fluorescent lights, etc.

Shielding is meant to work on electric field noise, not magnetic field noise. It won't do much for 60Hz hum, and, arguably, it won't do much at all, being an incomplete Faraday Cage. Though, in some cases, it has been proven to work well.

The "newness" of your components also does not have much affect on anything. The laws of physics remain the same with 60Hz hum. It's either there with an odd number of coils, or it isn't, when an even number of coils allow a full destructive interference of waveforms in equal amplitude, 180 degree phase difference.

 

[newpatch]

Thanks guys,

I mentioned that by electronics are new just to rule them out. My research also points to the classic hum..

Theoretically....if I remove my humbucker..there should be no hum right? since there will only be 1 single coil pickup..

dinkyguitar

 

[line6man]

Thanks guys,

I mentioned that by electronics are new just to rule them out. My research also points to the classic hum..

Theoretically....if I remove my humbucker..there should be no hum right? since there will only be 1 single coil pickup..

dinkyguitar

No, you will have 60Hz hum any time there are an uneven number of coils audible, and you will cancel hum only when you have an even number of RWRP coils at reasonably similar output levels.

One single coil, or a single coil and a humbucker will hum.
The humbucker alone will not hum. (Obviously.)
A single coil or  single and humbucker together can only humcancel if you add another source of hum 180 degrees out of phase, and at a reasonably similar amplitude. This could be accomplished with a dummy coil, though the impedance drop of the extra coil would kill some tone.

 

[TonyFlyingSquirrel]

I can tell you from experience in both Strat and Tele forms, the Quarter Pounder is a loud pickup with plenty of hum.  It sounds great as a pickup, but in between you may consider applying some noise reduction ala ISP Decimator or MXR Smartgate.  In the bridge of a Tele, it sounds huge, really full, but the noise comes with it to a certain degree.

 

[bagman67]

So just by way of hijacking this a little bit - suppose I have a battery powered amp.  Is the tendency for single coils to be plagued by 60-cycle hum going to be diminished/eliminated by removing the 60hz AC power source from the signal chain?

See, e.g., my old friend Dave Padilla's amp, the G1:

http://grid1.com/

Peace

Bagman

 

[line6man]

So just by way of hijacking this a little bit - suppose I have a battery powered amp.  Is the tendency for single coils to be plagued by 60-cycle hum going to be diminished/eliminated by removing the 60hz AC power source from the signal chain?

See, e.g., my old friend Dave Padilla's amp, the G1:

http://grid1.com/

Peace

Bagman

No. Once you have induced 60Hz hum into the pickup coil, it's going to be there no matter what you do with the rest of the signal path, unless you can generate an identical source of hum at a 180 degree phase difference to cancel it out.

Theoretically, however, you should see less 60Hz and 120Hz hum in a battery powered amp, because there is not a transformer in the amp, and you are starting with clean DC power with no 120Hz ripple.

 

[Cagey]

If you didn't have ripple-free DC running in your amp now, you'd hear it even with nothing plugged in.

Back when electrolytic capacitors dried up a lot faster than they do now, it was the easiest way to tell whether you amp needed a "cap job". Just turn it on with nothing plugged in. If you hear any hum, the filters were failing and it was time to change them.

 

[line6man]

If you didn't have ripple-free DC running in your amp now, you'd hear it even with nothing plugged in.

Back when electrolytic capacitors dried up a lot faster than they do now, it was the easiest way to tell whether you amp needed a "cap job". Just turn it on with nothing plugged in. If you hear any hum, the filters were failing and it was time to change them.

I said "theoretically," not "usually."
It's not hard to filter out ripple, and any half-decent power supply should give you well-filtered DC. If ripple should ever become an issue that you actually notice that you are hearing it, it's definitely time to fix up your power supply. :blob7: