Why is my amp requiring as much volume gain?

I think you've answered your own question re: input sensitivity. It is only really a problem if at max volume on the preamp you still don't have enough gain to satisfy your in-room max dB requirements.

One thing to keep in mind is that most preamp volume controls are more linear in the middle and upper control ranges and could possibly sound even better at the 12 o'clock position as opposed to the 9 o'clock position.

The difference in wattage output translates to less than 3dB in added volume potential. That's only a little bit louder at full volume. It's just not a dramatic difference.

The Bryston amp has an input sensitivity switch that selects 1v or 2v input voltage. Check with the owners' manual or Bryston to see if you're using the correct setting.

I once owned a Bryston 4B and noticed exactly what you mention, but maybe not to the same degree. I did have to turn up the volume knob a little more than with any of my other amps to get the same perceived loudness. But no matter the volume, that Bryston had the best, most controlled bass I've ever had in my system. When talking with Gilbert Yeung of Blue Circle and Mike Farnsworth of Talon Audio a few years ago at CES, both commented on how well Bryston amps do bass.

Thanks guys.I might check to see where the seting is for 1 or 2Mv and yess were not talking about going from a 50 to a 300 watt.Notice the newer maggies eat it up even more than before (went for III to 3.6) and they have always been hungry.Might at some point slap another Brsyton on.And Gunbei I will agree that the bass is nice with Bryston but I sold Krell for about 6 years and when I heard other amps we sold (Mac,Adcom etc-small shop) or in the field where I heard other gear saw or rather heard why so many speaker manufaturers used krell for demo'ing there speakers.Nothing else (Class or A/B)had the "grip" if not quantity of the Krell.Now that came part and parcell with a decent if brite high end (was told by freinds and amaggie krell was bad match since they had such stong resolution) an a metalic midrange I found clinical and etched.Fatiguing and not a good match for a Thiel defintely.Well I have a KSA300S I picked up froma a former customer but toild my buiddy (it's his maggie system actaully) that he should save money and not buy my amp so I found him Bryton which has (and this is general oppinionm) much better chromatics thrughout the frequency range.Yes good amps at a good price built to last.There is beter but you have to pay through nose (Levenson comes to mind here).Me I'd like to hear all the brew ha ha about the new John Curl Parasopund JC1 400 wat amp.Reviews I always take with a grain of salt but noticed more than one reviewer bought his review smaple and that makes me sit up and take notice.Not cheap at $K but think it may develope a Plinius like cult following given first few years reaction.
Thanks
Chazzbo