By Glenn Watt
The simplest solution to your most maddening problem
For the love of all that’s good, why is my magnetic pickup humming?
You’ve installed a magnetic pickup in your cigar box guitar, and the darn thing is making noise.
“Oh, just ground it to the bridge.”
That’s the advice you read in every online forum.
“I can’t ground to the bridge, ‘cause the bridge is wooden.” you think to yourself, fuming behind your computer, and wondering what your next move is.
Well, you’re in luck. There’s more than one way to roast this chicken.
The solution: Ground to a metal tailpiece.
The point in grounding to the bridge is to connect the strings to the ground loop.
The ground loop is all the components — the input jack, pickup, volume control, and strings — connected to a common ground, such as the back of the volume control.
So, even if you’re working with a wooden bridge, you can still get the strings into that ground loop, and get rid of that hum!
For example, check out this hinge tailpiece.
On the surface facing the cigar box, and just above the box lid, use sandpaper to scuff off a bit of the brass plating.
Then, solder a length of insulated hookup wire to the back of the volume control. If you don’t have a volume control, then solder it to the ground lug of the output jack,
Make certain the wire is long enough to comfortably reach the tailpiece when the box lid is closed. You can snip off any excess wire later.
Next, create a little space for the wire to reach the hinge.
As you can see in the image, a groove was filed in the edge of the box lid. Depending on your cigar box, you may need to drill a hole for your wire.
After that, cut your wire to length, and solder the loose end to the spot you scuffed onto the hinge.
Turn up the heat on your soldering pencil and / or hold it against the hinge for a bit. It’ll take a few moments to get the hinge hot enough to melt some solder on there.
Once you’re done soldering the new wire to the hinge tailpiece, you’re ready to string your CBG up and play it hum-free!
A hum-free cigar box guitar!
Getting your strings into the ground loop is key to reduce hum on your cigar box guitar.
It doesn’t take a metal bridge to pull off this feat; you can continue to use your wooden bridges.
Go ahead, kick back, and smile with your new-found trick: ground to the tailpiece.