OP you mentioned you had a lot of art work. I guess it is hanging on the walls. Unless there are a lot of glass on the wall surfaces, you’ll be better off. I’ve seen more than one person with a tons of hanging things from the walls, and ceiling.
Painting on canvas with different types of frames will collect frequencies differently than others. When the frames is convex with raised crown borders vs flat stock, they act a lot different. The second is all of the canvas have air space behind them. They act with a certain amount of absorption and diffusion as long as there is not a lot of glass (there is a place for that too).
I have seen rooms over dampened just because of too much stuff in a room, and not a single piece of acoustic anything anywhere to be seen. LOL
Heavy curtains are what I’ve always suggested and used. WHY? An untreated long wall with high ceiling is a hard thing to tame. Being able to open or close curtains over a long bare (or covered with glass) wall works wonders and you can adjust the amount of dampening too.
I say the same thing every time. Add as much room treatment as you can stand, then start at the bottom and work your way up. BASS (sub) first, NOT last.
Now you can buy just about any speaker you want and it will work. It has to be a real pile to not work from 80hz and greater with ok measurements.
How hard is it to get a speaker to reproduce 100hz to 18khz. 90+ on sensitivity? Personally I used 92% sensitivity wired @ 12 ohms and have for over 20 years on my mains. There is no bass in my mains at all. Kind of defeats the purpose of vibration control if the box is banging away beating on mids and tweeters in the same box.. A different box make good sense to me.. At least be able to limit the mains to 80hz and above..
DBA, Swarm, Second (after room treatment), not last.. If you really want to get fancy go with a OB or IB servo sub system. I use GRs 12" dual OB Servo subs.
Real eye openers vs any other type of sub system..
Happy hunting.
Regards
I’m BACK. Give me your cloths, Sarah Conner, Where is Sarah Conner?