I recently picked up a used MIM fretless Fender J. My first time playing a fretless, it sounded and played great, and I loved it. But I wasn't happy with the way the volume pots gained 75% of their volume over the last 25% of their travel. I did quite a bit of research here on TalkBass, and decided if I would install linear pots, it should resolve the "issue". Since I would be putting on flats at some point in the future, I decided I'd go with 500k pots for that little more tonal range. I ordered CTS 500k linear split shaft pots (and shaft sleeve adaptors for my set screw knobs), from GuitarPartsResource.com. By the way, I was impressed with their prices and fast shipping. I'm inexperienced with wiring and electrical work, but researched that also, and the mod came out OK. I left the tone pot stock, and replaced only the volume pots. First, the issue with the steep volume gain was not resolved, it's no better and perhaps even a pinch worse. The tone is also different with the new pots. The neck pickup didn't change a lot, but seems a pinch muddier. The bridge pickup now sounds more like the neck pickup, a pinch cleaner than the neck pickup, but it no longer has that classic J Bass bridge pickup sound. The 2 pickups now sound too much alike. Let me clarify, it's not a bad sound, and it's playable, but I can't come close to getting a Jaco sound out of it now, where I could before doing the mod. First, could this be a case of botched installation? I put the new ones on exactly like the old. Could the 500k instead of the stock 250k make that much difference in tone? GuitarPartsResource.com says the linear pots are "for tone control only", and in a guitar I can see that. But based on my research, this should be OK for bass. I'm ready to order CTS 250k audio pots to try to get back the old sound, as I unfortunately garfed up the old pots taking off the wires. I'd appreciate any thoughts or input you all might have on this.