Passive pre with Bryston 7B ST??

How many sources are you running? If only one, you might consider the EVS attenuators--they go right on the power amps and save a cable and some connectors. But in general, I don't see how a 10K ohm passive could fail to work with the 7B ST's. The passive/active debate will surely never end, though in a recent post almost everyone liked passives best. Is there any way to try a passive risk-free? I've had high end active preamps--e.g. a CAT SL-1 III with its signal path factory-simplified, and prefer a DIY passive. But such knowledgeable reviewers as Martin Colloms believe that even a top CD player offering digital volume control sounds better through a top active preamp. In the end, it may be a matter of what aspects of the sound matter most to you--though I don't feel I'm losing anything with a passive.

...that's how it's suppose to work. Having sencitivity of .8V and the source output of 2V you won't need any extra gain.
Try it with Creek OBH14 and it'll smoke Bryston BP25 in your case.

Agree with Rdg. I have tried Reference Line Preeminance 1A with 4BST and later on 7BST's driving a pair of Maggie 3.5Rs. I gave up and went to active preamp. Try a tube preamp for your 7BSTs...

As an alternative you may want to try an Adcom GFP 750. It's a Nelson Pass design, runs either active or passive, and can run balanced in/out. You can pick them up under a $1k here on audiogon but make sure you ask questions. At one point there was a run of bad ones, which the factory cheerfully rectified. High input impedance in the Bryston and true balanced input is a beautiful thing....when you go passive.

I have 2 passive amps, the placette and the EVS attenuators.
I also have had the BAT, Thor TA-1000, Cary slp-50 and now the blue circle BC-3 Galatea line stage.
The passives need to be matched with the right source and amps. You have to drive your amp to life. I could not get either passive to drive my Bel Canto SET40 to my liking. There was volume, but no life. Yes it had bass too, but it was missing something. Paired with the Evo, the sound was very detailed but on the lean and sterile side. Very detailed, but to the point of distraction.
The way to go is with a quality active linestage. The BC BC-3 did it for me. The stepped attenuators, simple circuitry and great design make music. The sound is detailed yet doesn't distract. The bloom and presence are all there.
Great pace and it sounds alive. A drum kick is felt, not just heard. Vocals have air, depth and a pleasant natural presence.
There is no right or wrong in what you prefer. Everything matters in the audio chain. Keep things as simple as possible when dealing with the source signal. An active linestage is a great way to manage the type of sound you are looking for.
Look for a simple design in an active linestage. The Cary SLP-50 is a good eample. The BC-3 is more refined with a very well designed power supply. Don't ignore the volume control. You would be amazed how many $8K preamps use a $25 volume control. Go with a stepped attenuator setup if possible.
mike