Wow, you guys know your stuff.
I looked up "Golden Section" and found lots of speaker placement instruction, but not much re: optimal listening room.
Will proper speaker placement offset problems created by cube? This size room does allow speakers to be placed far from walls.
Would 20' x 24' make a difference? Any idea what would be optimal? I have a lot of leeway at this point.
The ceiling won't be 22'. What would be optimal?
Thanks a ton.
Optimal Listening room...
This is a huge topic...Best thing to do is to keep using the search function for a info as well as question us. There are a lot of friendly and knowledgeable people here that are very willing to help out. Acoustics is mathematical and scientific, general acoustic corrections are not to bad as long as you know some basics.
By the way, a 22' ceiling with no acoustic treatment would present its own problem and that would be late reflections which would really mess up the quality of the system. At this dimension we're probably talking about moving from reverberant reflections to almost an early echo.
Every room is a challenge especially if it is shared by other family needs, in other words, it is not dedicated to audio/video equipment for the sole purpose of maximizing the reproduction of music or video playback.
Proper speaker placement reduces undesirable effects due to room dimensions but only to a certain degree and at certain frequencies...it can also increase other frequencies depending on the wavelength...you will have much more to deal with especially in a perfectly square room of 22 x 22 x 8 so try to avoid those dimension that are square.
As far as the wall behind you opening up to the room behind, yes it will have some effect but should not be to big a deal. I knew someone who had a large closet against the rear wall behind the listener. They complained about a noticeable peak in the mid bass frequencies. It turns out that the closet had its own standing wave based on the wavelength of the offending frequency causing a peak. If it were me I would put up a heavy drape which could be easily opened and closed. This will reduce echo from that room back into the main listening room. That room will have its own standing waves which could be detected if you're a critical listener. If you can't use a drape, a large portable absorption panel could be positioned behind the listening sofa to reduce any sound from the back.
There are better room dimensions which are more conducive to a better response that others and you have started your research by the search criteria that Kach22i provided. That is a great start but it also implies that you are starting to build a room from scratch. Keep in mind that you can get reasonable results from a regular room with acoustic treatment, just try to stay away from perfect squares. Most of us have to deal with what we currently have in the house to use and go from there. A great many times this means researching, calling acoustic control companies for advice and using their products to tame the offending reflections or standing waves to a minimum. Do another search here for room acoustics or acoustic treatments and read. Try this for starts:
Room acoustics
20 x 24 would make a difference but not much. You can get away with those dimensions if you utilize some acoustic panels in strategic spots. Ceiling height, keep it around 8 to 10' for a good treatable height. Go with a acoustic companies recommendations for treatment, should be minimal, perhaps a few ceiling panels at the early reflection points and that should be it for the ceiling. Budget about $1 - $2K for some acoustic room treatments. Same goes for the first reflections of the side walls too. Don't forget the panel behind your listening position. The link above in the previous paragraph has a few good links to acoustic company websites.
Recomendation:
Start by positioning the speakers and listening sofa first. Listen for a while and experiment by moving the speakers and chair around some, six inches forward, backward, side to side. Stay out of the front and rear 1/5 of the room and you should be able to keep things listenable. Read some of the threads in this site and get some ideas. Don't get to squirley with all the technical data or products, keep it simple for now. Then call up some acoustic treatment places recommended in this forum and get some advice.
If I may quote Roberto, "Happy Listening"
Sam
