I have a 3pole delta blues pick up from cbgitty. Comes wired with a plug in. Do I need to ground this unit?
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I have a 3pole delta blues pick up from cbgitty. Comes wired with a plug in. Do I need to ground this unit?
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Why do coil pickups buzz?
the short answer is "Metal Detectors"
>metal detectors?
yes...metal detectors.
Metal Detectors work by squirting out a tiny blip of radio wave, and then listening for a reflection to come back to it.
All metals reflect radio waves.
Air Traffic Controller keeps track of airplanes with radar, by detecting the reflection of 2.8ghz radio waves off the metal skin of the planes.
Treasure hunting metal detectors blip out and listen for the reflection of 15khz radio waves off of metal coins, metal belt buckles, metal rings, etc.
How do metal detectors "listen" for the reflection? with a "coil" antenna wired up to an amplifier.
A guitar pickup is a coil wired up to an amplifier.
Now we are getting somewhere; the pickup is acting like an antenna and 'picking up' all kinds of ElectroMagnetic (radio) noise and sending it to the amplifier. Fortunately it is not a very good antenna and can usually only pick up nearby noise reflecting from the strings, the volume and tone potentiometer bodies, the wiring.
So why does grounding the strings get rid of the noise?
Well we need to understand how metal reflects radio waves.
Metal absorbs ElectroMagnetic waves as a charge across the metal, one end a tiny bit more positive, the other end a tiny bit more negative; sort of like a 0.001v battery was just connected to either end of it. A charge difference across a conductor will have a current through it.
this is how the car radio works. When the positive part of a radio wave hits the antenna, it gets a positive charge and a small current runs down the antenna into the radio, and when the negative part of the radio wave hits the antenna, it gets a negative charge that sucks a small current back up the antenna.
Now back to metal reflection: any current has a magnetic field around it, producing an electric field, and that yields an ElectroMagnetic emission, effectively reflecting the radio wave back out. Much like throwing a baseball at a trampoline, it absorbs the energy, then sends it back.
so any EM noise is putting micro charges across the strings, causing current in the string, and the coil picks up the magnet field part of the current. But grounding the string defeats that, by 'sucking' the charges down to 'ground' instead of flowing back and forth in the string. Our meatbag bodies are just conductive enough to also suck up that tiny bit of charge which is why touching the strings can kill the buzz.
So where does this noise come from? Every electric motor and fluorescent light has coils that emit 60hz/50hz radio waves, but the source is often the amp itself. Mic level, instrument level, line level, pre-amp, EQ, power amp, power source, these are all at different internal voltages, and the "step down buck" circuits inside the amp to make all these different voltages are not delivering perfectly clean power, and they can also bleed some noise through them. Even battery powered amps have these same step down buck circuits that are not perfectly clean and also bleed noise. The noise goes through the power circuits, up the instrument cord, into the coil as though it were a transmitter, reflects off the strings, and then back into the coil and back into the amp as buzz/humm/noise.
Connecting the strings to the same 'ground' as the coil bleeds off this EM charge instead of letting it reflecting back to the coil.
YRMV https://cigarboxnation.com/forum/topics/cb-gitty-single-coil-pickup
Thanks for all the advice. I am putting it in a licence plate guitar. We will see how it sounds.
Well, how does it sound? Can we hear it, can we hear it?
Karen, I think you’re asking if you need to ground the the pickup to the Bridge? Yes, a good idea, it’s actually standard practice whether it needs it or not, even in brands like Gibson, PRS,Jackson that are known for humbuckers? But the Delta pickup is a single coil pickup, so yes you will ground it to the Bridge or anything touching the strings? Good luck with your build :)
Actually . Not all mag pickups need grounding . Many humbucker pickups you can use straight to Jack because they were designed to "buck the hum" hence the name " HUM-BUCKER" . Other shielded / treated pickups can also pass the test . Some are much more effective , even labeled "silent ". Not to mention Some folks would rather not have their guitars grounded due to stage / shock hazards etc .. Many Pro musicians play un-grounded guitars , or with a ground switch to use if needed.
I can't speak for the delta pickup , because i have never used them . but your best bet is to try it without , if it is hummy . try grounding it . usually this only involves running a wire from the back of the volume pot to the bridge (if metal ) . but remember . lights , other appliances , radios, other machines on the same line ... etc . can all have an effect on hum . sometimes just plugging your amp in a different room makes a huge difference .
good luck.
ps .. your replies are not showing up . please click the "html editor" in top right corner befor you post . (its a site glitch )
Hi
, all magnetic pickups are grounded, prevents hum, except low impedance pickups. Taff.