Room Acoustics: Long End vs Short End placement?

I have a room that is 12X14. I currently have the speakers on the short wall about 7 ft apart. This placement produces only average performance from the Acoustic Zen Adagio. I have identifed a slight echo in the long wall corners which is creating both too much mid bass which lessens clarity. Therefore, I am going to try the long wall which is almost 12 feet of heavy glass windows, no wall at all. This will give me a bit more flexibility with placement and distance from the speakers, and can use a pair of AZ Hologram 2 speaker cables which are too short for short wall setup. In addition, I am going to try to squeeze in the left hand corner a 6ft tall bookcase stacked with books and thick textbooks. and magazines. This should at least dampen one corner---the right corner will be the site of a vertical component rack. I am concerned about a few problems in the new set-up. 1) the intereaction of the speakers with that plate glass wall of window behind them 2) Across from the speakers sits an 84 inch overstuffed couch. Behind the couch is a backwall which opens into an efficiency kitchen. The majortiy of the wall is approx 45 inches high and probalby particle board. Therefore, I am concerned about first or second wave reflections off the backwall of the kitchen.... MY Goal: to get the speakers to sound smoother and musical(as opposed to overly analytical and bright) with solid imaging. (The Adagios is a great speaker with outstanding resolution and believe it should/could sound better. I have to find some damping method for the right corner of the long wall set-up---there is no room for another bookcase. There is an overstuffed recliner which is the listener's throne in the old set-up, which always seemed to be too close to the speakers. Across, from this chair is a 43 inch panel TV which I cover with a heavy bedspread when listening and provides some damping. As you can imagine, the wife just loves the look of the bedspread over the TV.... BYW, there is an 7X7 throw-rug on the floor...... I welcome all advice and opinions. Thanks, Jim
There are to many variables in your set up to give good advice . You will have to move stuff around and experiment till it sounds the best . If you require longer cables , most audio shops have demo cables they will lend you , if not borrow from friends . Glass is one of the worst things to have in a listening room , I hate to say , heavy drapes , but this will help , if your better half will allow it , ( half or two thirds , what ever it works out to these days ) .
i have my adagios along the long the short wall firing into the kitchen as well...havent figured out what to do yet.Drapes i guess are your best defense for the windows.I did place panels in upper corners behind speakers and that eliminated the secondary echo,dont want to deadin it completely i believe.yes moving it around is a pain in the ass but rewards are worth it huh.I have moved my couch back as much as possible,like the specs in the manuel.Robert know what hes doing.i also believe having them as far as possible from back wall give best sound. stage
Digs, If I go with the long wall set-up, I doublt I can get the speakers out more than 18inches from the back glass wall---that would even be pushing it. There is a panel TV on the left side of the room which can only be moved about 1 foot. Drapes are not an option becasue I am only renting, but there are vertical plastic slats shade which can be closed. I doubt they will make that much difference. However, your corner panels idea is good and do-able, but that will involve some bucks. As I mentioned I have a book case that can be moved into the living room that is full of books. Of course, it may also provide a two day back ache....BTW, What are you using for electronics to drive the Adagios?? I have a Creek SE5350 Classic (85RMS) but I have a suspicion it is not quite right for the AZ's. The amp can often sound bright, despite room aberrations

To Tmsorosk, You are right about the glass, As I mentioned to Digs, drapes are not an option. My better half has giving me carte blanche, but I know that isn't going to hold once I start moving furniture around. Nvertheless, I am going to give it a shot. Thanks guys, Jim
hey jim im using sim i5.3 amp and cd player.I would suspect your amp is a little on the british bright side.I am using auralex from music direct...there are better but it i said you dont want completely dead.If you can only move out that be it...try toe in to resolve sound stage.