There are internet sites that have room mode calculators, displaying in 3d where standing waves appear in the room, which is determined by the dimensions of the room. You put your room's dimensions into the calculator, and a 3d drawing appears, showing where in the room nodes are located. If you place your speakers and listening position where no such nodes appear, you have minimized the resonances of the room itself. Room treatments are therefore minimized as well.
What are the limits of room correction/ treatments ?
My old listening room was open to other parts of the house allowing excess bass energy to escape and had a high 13ft. ceiling. Clear tight bass and open clear midrange even when loud. My current room, while bigger ( 17 x 21), is boxy with 9' ceilings and a single door entrance. You can really hear the room getting in the way on many recordings, esp with louder complex recordings. Can room correction + treatments really make my current room sound like the old one?