Which Preamp for Bryston 4BST. BP-25 or Rogue 66

I am in the same situation as yourself..looking to change from a SS BP-25 Bryston preamp to tubes.
As pointed out to me by someone in the know..you have a very good preamp amp with the BP-25 so make sure that you look for the same or better quality tubed preamp if you want to see a significant improvement.
The two tubed preamps suggested were..Rogue Audio 99 or BAT V50.(something like that)
I was very excited with the fact of changing to tubes but that statment brought me back to earth and changed my way of thinking.
So am I on the right track only looking at tubed preamps in the $2000-$3000 range and nothing less.
Sorry I didn't answer your question but hopefully we can both benefit from some further responds.

There is a Blue Circle C3 Preamp available on Audiogon and its still available.Check the reveiws on that fine piece.
A liitle more money but a avery good preamp.

As stated above I to have a Bryston 4B ST power amp and had the opportunity to audition,in my own system a Blue Circle
BC3.1, and all I can say is..WOW!!!!!!
In all fairness ,the BC3.1 is a more expensive preamp than my previous Bryston BP 25 preamp,but the improvement in sound is worth every penny.
Before you buy try a Blue Cicle preamp.
They have a excellent entry level preamp BC 21.
There is a couple for sale on Audiogon at this moment.
Customer service is EXCELLENT..
Happy listening..