I don't know if anyone here has been down this road with one of these warwicks but I am at my wits end. I have had this bass for 2 years and had problems the whole time. I have an Ampeg B4R and a 6/10 Ampeg cab and they work perfectly I know this because I have a stingray 5 and it is crystal clear and loud without distortion or farting out. But with my jazzman it craps out and sounds like speakers are going. I just had the preamp replaced a month ago because it broke. I had extensive custom work done to the neck and love the bass but I can't take the electronics anymore!!
is there a way to use the current pickups because they are passive and wire them direct or should I put replacement everything in pickups to pre amp. I don't mind spending the money I just want it to sound as well as it plays. I thought bart would make a good replacemet or basslines. Does anyone know where to get all the replacement parts I need to order to do a complete redo? 
