I installed some Dimarzio Ultra Jazz pups in my Eshenbaugh bass a few weeks back. Tonight I was playing through my headphone setup and I heard cracking noises when ever I hit the strings hard. And, depending on how I positioned the bass, the noises would come and go. At first, I thought that is was the battery but the noise was present in passive mode also. h-m-m-m-m Then I looked in the preamp compartment to see if anything had come loose and I found the source of the noise. The Dimarzios come with three leads, red, green, and gray. The only two needed are the red and green. So I coiled up the gray lead and neatly tucked them away. It is the gray leads that are vibrating against the shielding and causing the noise. I uncoiled the gray wires and let them hang outside of the compartment; the noise is gone! The installation instructions make no mention of the grays wire at all. What am I supposed to do with the gray wires?
JR, Are these an older set? The newer Ultra J's I've seen have red (hot), green (cold), plus a black and white which usually get connected and left as is. I'd suggest taping them up, with electrical tape or heat shrink tubing. Sounds like they're hitting the shielding foil and shorting something.
Looks like they haven't updated their web pages yet - here are the dimarzio ultra jazz instructions, which reference 4 wires (red,green, white,black). This ties in with my own recent ultra jazz 5 experiences. I've seen Carvin pups with an extra third shielding wire for hum cancelling, this usually goes to ground. So you could try that, or just tape it up as I suggested previously.
DUH...you're right. I'll snip the ends off and tape them up. But, what are the gray wires for? I'll call Dimarzio today and post the answer.
The Gray is a ground. The Sadowsky huncancelling p/u's which are designed by Roger but manifactured by DiMarzio have this Gray wire.
Thanks! I just got off the phone with Dimarzio tech support. - The gray wires are to be grounded. Its purpose is to reduce noise when the player is not touching the strings. - The gray wires are only on the 5-String Ultra Jazz pups. These pups are wired in series internally and therefore do not have the black and white wires [for parallel operation]. - I am one of many callers on this same subject. The installation instructions are being rewritten to include the gray wire. Thanks Again!