Like you I have a large room to fill with music. My room is 40x16x10 and there is a large opening to an adjacent room that really almost doubles that. My amp puts out 285w into 4ohms so it’s not super powerful by any means but it has some juice and is very musical!
I ended up going with and highly recommend the Monitor Audio Gen5 Gold 300s! Their newest in the line...They are gorgeous with their Piano Ebony and leather finish, and are even better sounding than they look!
The tweeter is the best I’ve ever head and I’ve listened to about every brand for 30 years or so. They are incredibly detailed and have a WOW factor on both the attack and decay! Yet they are never forward or in your face. They just present highs like cymbals like never before, just adding them into the music in their proper place when in the past with other speakers they were muted or not even heard.
The mids are beautiful and life like making Voices come to life. The likes of Norah Jones or Stevie Nicks jumps out at you with such a sense of realism that they sound as if they are there with you in the room!
The bass is deep, tight, and fast bringing fullness to any track you are listening to! The bass can also get down right crazy listening to tracks from the likes of the Dirty Heads who put that exaggerated bass into the recordings. The Gold 300s puts it out in spades making one look for the 15” subwoofer, that doesn’t exist, in the room! Lastly the need of sound output is not a problem, they play big and really need a large room to fill with music. They fill my space with ease and I find myself setting the volume where I did with my last set of speakers only to find myself coming back and turning down the volume. They can play loud!
The Monitor Audio Gold 300s are at the bottom of your price window at $8000 but as I have found out will out play most anything in their class!
TAS has given it a editors choice award two years running. There a lot of very positive reviews online about it here are two. They deserve an audition!
https://totallywired.nz/loudspeakers/monitor-audio/monitor-audio-gold-5g-300-loudspeakers/
https://www.theabsolutesound.com/articles/monitor-audio-gold-300-loudspeaker-1