Im putting together a Jazz bass with Nordstrand NJ4SE pickups (each of which has the usual black and white wires) and J-Retro preamp. Question is, will I need to shield the control and/or pickup cavities, do you think? And will I need to connect the ground on the J-Retro underneath the bridge, or will this wire be redundant? It will be the only ground wire on the bass, I suspect, as the black/white leads from the Nordstrands will just connect direct to the pins on the pre-amp (I have some header pin connectors for this). When I've put EMG Js in two of my basses, there was no need either for shielding or for a ground wire to the bridge. Very interested in your opinions on this. I do want to keep hum to a minimum as much as I can (that's why I chose these pickups rather than the single coil Nordstrands). But I don't want to waste time on a superfluous shielding job or have unnecessary ground wires connected to the bridge and strings. My basses with EMGs are almost perfectly quiet with no shielding or grounding (different sort of pickups altogether, I know, being active "in themselves" rather than passive). What do you think? EDIT John East, the J-Retro designer and manufacturer has answered this query for me and said I would need to connect the bridge to the ground wire (John is a great guy to deal with and always extremely helpful - thanks a lot for your assistance on this, John). He also told me the Retro itself should be fairly quiet without shielding. But I was still wondering about the need for this, as John hasnt used his preamp with the Nordstrand pickups. Think Ill take Johns advice and put a link to this thread in Careys forum another really good guy to deal with who seems to find time to help you out. Im going to start a thread in Miscellaneous about guys like this John, Carey, Rob Green at Status . hoorah!