Hello, I need help my problem as seen on my pictures.
This is my first Electric Upright Bass, I built from Motolla Libellula EUB Plan, 35 scale 4/4
And I use Piezo Under Saddle Pickup, I built from coax (from Experiment Musical), and the PreAmp I bought from Walter Cafe PZP-1.
there is some sound interference when I put my hand on the top of PreAmp cavity cover, all inner cavity I shielded with bronze foil from StewMac.
I've check the ground of pot and the ground of jack connected with the shielding, is that the problem?
And what should I do.. thank's and I will soon post the picture of this guitar...
And Merry Christmas to all of you...
edit: picture pickup ground (black wire) I've released and move to the one other pin on jack (the medium tall)