If you want to limit what gets to the speakers so you don't blow them, then I would set the pre volume to something like 1/2 or 2/3 with the Bryston cranked down, then spin those up to as loud as is safe for you and your speakers. Then..you have a pre-set limit in place.
Or, just set the Bryston pots to about 7 out of 10, and be careful with the pre volume.