I've heard a number of rooms with all sorts of treatment. A friend has a ground up special room that costs more than the average house (has the full design/build supervision by Rives). I like the room myself, but, a number of other friends find the result offputting (too cold and analytical sounding). This Rives room is actually one of the better full blown treatments I've heard; a number of other heavily treated, professionally designed rooms I've heard sound REALLY bad to me (they exaggerate the current audiophile trend toward lean, detailed and lifeless sound).
Many of the better rooms I've heard were normal rooms with a lot of "treatment" in the form of bookcases, art objects on the walls that act as diffusers, effective use of carpeting on the floor in front of the speaker, and most importantly--very carefully located speakers and listening position. I've even heard a room that is all masonary block that sounded great through the use of some very pleasing to look at tapestries.
Myself, I have a room with open spaces around the speakers, a lot of clutter around the perimeter, and tube traps in the corners--that is enough.
More than anything else, it is the proper location of speakers that matters--most rooms have at least one decent location. The trick is to find the proper location and to make the hard choices/compromises--aesthetics/space utilization vs. sound, decent sound for multiple listeners vs. ideal sound for one listener, etc.
Many of the better rooms I've heard were normal rooms with a lot of "treatment" in the form of bookcases, art objects on the walls that act as diffusers, effective use of carpeting on the floor in front of the speaker, and most importantly--very carefully located speakers and listening position. I've even heard a room that is all masonary block that sounded great through the use of some very pleasing to look at tapestries.
Myself, I have a room with open spaces around the speakers, a lot of clutter around the perimeter, and tube traps in the corners--that is enough.
More than anything else, it is the proper location of speakers that matters--most rooms have at least one decent location. The trick is to find the proper location and to make the hard choices/compromises--aesthetics/space utilization vs. sound, decent sound for multiple listeners vs. ideal sound for one listener, etc.