Hi. I'm thinking of modding my American Standard J-bass with a preamp and/or new pickups. Basically, I love the warmth of the bass' sound, but wish I had more highs (this bass has a rosewood board and alder body, but I slap a lot). I'm seriously thinking about popping in an EMG bass expander knob or EMG concentric bass/treble knob or EMG sweepable mid knob. So what have you done to a J-bass? How did it turn out? Advice?