I've had the 614 and 414 which is a keeper for sure,
...the active Raspberry 614 was a great bass (real slap machine) and I now wished I hadn't sold her now so quickly, but at the time I thought it had too many controls for me, and yes the pre-amp can make this bass sing high treble and super deep bass notes, but with it flat it's goes a little quiet....I gota say though the 414 is a super bass, red hot pups too, fast neck and sublime finish, can't go wrong
sometimes some new old stock ones appear on Fleabay from a compnau called whybuynew...worth checking them out