Hi everyone, I'm new to the forum and just got into instrument building.I've made a mountain banjo, a couple of stick dulcimers and I'm now near the end of completing 2 CBGs. So I've been looking at the diagrams that google throws up when i search for them. One thing that puzzles me is the wiring of the black wires on to the pot chassis and the 3rd tag. I have some electronic experience, and I can understand the connection of the red wires from the piezo to the pot tag 1 and tag 2 and out to the jack socket. Why doesn't the black wire go directly from the piezo to the jack socket?

The way the diagrams show it( with black soldered to pot chassis and tag 3) would put a short circuit or zero ohms across the socket output, when the volume pot is turned down. I would have thought putting a short circuit into an amp input, would harm the amp, or would it?

Maybe someone can explain this, thanks in advance, Mike