This is my current go to fretless bass, the Ibanez SRF705. It has 2 magnetic Bartolini MK1 pickups and under the bridge piezo pickup. There are 3 volume knob for each pickup, 2 band EQ for both magnetic and a tone control knob for the piezo. So, essentially this bass came with tons of tonal options. The thing is... I've just got USA Bartolini MK5CBC pickups for quite a bargain price. I don't have any problems with the stock pickups & electronics, so actually it's not a necessity buy. FYI, the MK5s are direct replacement for the licensed MK1 pickups and they have different coil configuration. The MK1 has split reverse-P coil inside, whereas the MK5 has full blade dual coil and can be wired as dual coil (series or parallel) or single (north or south) coil. For simplicity (as the bass already has so many tonal options), I might just wired the coils in series and be done with it. From what I've read, fretless will not get any advantages from parallel dual coil as it will result in creating mid scoop sound whereas fretless sound should be more focused on the midrange. Am I wrong? To enable coil switching, I need to install one or two mini DPDT siwtches. I opted not to go to this direction as I'd like to keep the bass body original, so drilling extra hole(s) for the mini switch(es) is not an option. But there is always another way... I could change the stock volume pot(s) to push-pull pot type which basically has DPDT on-on switch integrated. This way I could have the options of series dual coil or single coil for each MK5. The last option seems to be the direction I'm heading, but... I'm still not sure whether single coil pickups will be useful for fretless sound or will the result be worth the effort, as again, the bass itself has already came with tons of tonal options with the stock MK1 pickups, the piezo and the active electronics. I might just sell the MK5CBC. TB-ers, what say you?