Help : Passive or Active?

There was a thread on this just a few days ago, you might want to search on passive vs active pre and see what has been recently written.

The adcom 750 pre is both active and passive.

I have an Adcom 750 and in use would say in passive mod the sound can become a bit thin if the interconnects are really long 2 meter+, and a passive may not give the best if it's not with the right equipment. An active preamp adds a tiny bit of grunge but also has a powerful signal that does not get ruined by long connections or strange componenent interaction quirks.