Naaa, all passives are different, I just tweeted you the question, but it depends what pickups you're using.
For example, Bartolinis sound fantastic with a pre, but passively their output is very low. Get some Dimarzio's or something wound hot into a bass with no pre, it'll blow your head off. I certainly wouldn't base a decent passive setup on the OLP you've got
I had an OLP with a Bartolini MM and an East 2 band, that was the only active bass I've ever liked
Si