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Anyone have any clever tricks for grounding a magnetic pickup in an acoustic instrument.

This particular instrument is a Weissenborn style guitar. The saddle is brass but set into the bridge like a fret. So no sneaking a wire under the saddle. I thought maybe adhering some conductive material onto the bridge plate around the pin holes for the strings to lay against, but the holes are a strange pattern, so its not so simple as just lining something straight against the bridge pins. Maybe conductive tape on the bridge plate, but then how do I solder onto it (I guess I could outside the guitar.) And the last challenge, there's significantly less room to maneuver inside this instrument.

Conor, you’ve hit on most of the suggestions I would make already. A custom version of the “platemate” to suit the pin layout would be the way I’d go. How tight is the access in this weissenborn?


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If there is no noise when plugged in and amplified, then no need to ground the bridge or strings.

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The difficulty, as a repairman, is being able to simulate every possible environment a guitar might ever be used in, in terms of electro-magnetic interference. Since you probably cannot, I would lean towards giving my customer a string ground. This way, they don’t show up somewhere to play only to find their body has become an antenna and there’s no practical way to ground it while playing the gig.

I suppose, as an alternative, you could advise your customer to carry a roll of aluminium foil to gigs and shield themselves by simply wrapping themselves up like an Egyptian mummy and wiring themselves directly to their amp chassis. Running a string ground is a less visually spectacular solution but one that could be more appropriate depending on the type of venue one’s customers perform in.

heres an easy solution I came up with and have been using for years. make a duplicate saddle out of carbon fiber. carbon is hella conductive and works just fine for saddles as most piezo or ribbon transducers are shielded (grounded) on the outside via the foil or the woven shielding. if its a vintage weis then this will not work as the saddle is an aluminum bar, but this trick will help A LOT of luthiers. i use the carbon fiber in my necks so ive always got anything from .025 to .125 laying around. the .125 is what you want for most guitars because you can machine it down to 3/32" if need be. its not bone, but its hella hard,slick when polished and kkills two birds with one stone.

The access isn't terrible. This is the solution I think I've landed on, and I should be able to work inside the guitar with maybe only a little more cursing than normal.

Hahaha, you know what's a lot of fun? When the customer sends you a video of what is going on, and then brings his battery powered fishman acoustic amplifier to your shop, and experiences no problems whatsoever. So we guess at a solution to a potential problem, fix it, send it home, and then get a new video just like the first one.

It's just so strange. I suppose my customer might be a better antennae than me or something? His amp is battery powered so the problem is not dependent on the specific electrical context. I suppose there could be more interference at his house? I get no ground hum at my place. He gets it at his.

Haha, he already suggested attaching a wire to a pinky ring and then to the endpin on his guitar.

Interesting solution. I'll keep it in mind for the future. It won't work in this situation as the saddle is a brass bar set into the bridge like a fret.

Is he playing in a room with a fluorescent light? There’s a pretty decent coil in that ballast.

I was going to ask him that next time I see him.