I have a Modulus w/2 soapbar pups. I have no idea what they are. The existing preamp was sort of homemade looking thing (no markings and TBrs said it looked homemade) and the bass itself exhibited some bizarre EQing from the preamp so I bought a Bart 5.4 preamp to put in it. I am not a tech...and am a tad nervous about doing this but I was going to give it a try. The only necessary connections that need to be made are the pups to blend knob and the ground from pup to the new vol knob. weeeelllll each pup has a set of 4 wires coming from it...I have no idea what to do with them. I'll be contacting bart tomorrow but any ideas?