Adcom GFP-750 pre with Bryston 4BST amp works?

Passive balanced it should be fine. There are mods you can do to make it even better active.

I cant answer that directly, but I hust hooked up an Audio Research LS-3 with my 4b and its a great combo. Better than the BP20/25 that I had. Great deal for 600-700$

I had this combo for one year and it sounds great. I prefer the preamp in active mode though. Just upgraded to 4BSST and it is even better. Have to spend a lot more to get better.

Interesting I had the Adcom and preffered the pre in active too.Bummer was I had the whole stack (GCD and 5802) and it was just too much juice for my little 805 Matrix B&W's.Sounds like a good combo to me but I might want to try a Bryston 20 or 25.Ultimately if you have the speakers for it the active Bryston X-over.It would be a and all Bryston sound and be a bit more but might be better.But the Adcom is a hell of a good pre-amp if you have not problems with switching electronics.Adcom's could be built a bit better.

Ivanj, what mods to the GFP-750 do you suggest? Thanks
The Adcom sounds better in active to me but my Marantz CDB is said to lack dynamic drive and the active pre may compensate for that.

Basically the mod consists of upgrading the caps to Black Gates. I haven't had a chance to try it yet myself but I am told it increases transparency and removes any hint of edginess that some may find in active mode. Email me directly for more info.