Active EQ Basses: I know it's an unpopular opinion, but apart from an old Westone Thunder 1A, I've never managed to get the sound I want out of a bass with an active pre-amp. I've owned a few, including StingRay's (2EQ), an SB1000, a G&L L2000 Tribute, and a few others. The SB, 'Rays & G&L were nice to play, but I couldn't get that sound. Went back to a passive bass, and there it was.
Flatwounds: tried them, didn't get it.