I'm a bit experimental with bass building and revamping. I have a jazz bass in which I routed out the bridge pickup to fit a MM style humbucker. I installed a 2-band active preamp. Here's my dilema. I have both a bartolini Jazz bass neck position pickup and a bartolini MM style bridge pickup. I have everything wired correctly (so I think). I'm getting good sound out of the bass however I notice when I turn the blend pot to only have the neck pickup (Jazz pickup) on, play a note and bend the string; the volume kinda cuts out when the string is bent. It's weird. It's kinda sounding like a wah, flanger effect. Any reason as to why this would happen. It doesn't happen when I put full blend on just the MM pickup.

Do I just have a bumb neck J pickup? Any ideas?

Thanks for your help.

what is the model number on the neck pickup?

ok....this is what is carved on the bottom of the pickup 9W544-L

Well, I don't know if this is the reason or not, but the 9W4 is a quadrophonic pickup. There are 4 coils in it, spaced for a jazz bass. It may be that you are moving the string enough to get out from over any one coil. The "L" also usually indicates a bridge pickup, so this might make the problem more noticeable if it were used as a neck pickup.

I also seem to recall someon e mentioning that the 9W's were somehow inappropriate for MM+J setups. I also recall not understanding why, but I have seen a post somewhere indicating that. Might be worth trying to scare up a 9J1 to see if things get better. Bartolini would know best, obviously, but they can be hard to get in touch with.

Thanks alot. That makes alot of sense about bending the strings past the coils. You've been very helpful. I'll see if I could get my hands on another bartolini.