Problems with room acoustics??

I have a pair of Acoustic Zen's Adagios speakers, Creek 5350SE Classic integrated amp, and a Rega Apollo CD player. I have a room that is 12 ft wide and 14ft long. The Adagios are 50 inches high and are placed on the short axis wall which is not straight but juts out approx 12 inches on the left side. There is a wall of windows on the right side. I sit approx 7 ft away facing the speakers which are 6 ft apart( tweeter to tweeter) My problem seems to be a larger than life soundstage with some lack of focus or pinpoint imaging. There seems to be too much upper mid-range or resonance. The Adagios are a significant jump in performance from the Silverline Preludes I previously owned.... The room is moderately furnished with two overstuffed furniture pieces and a small area rug. There is also some slap echo in the room....Therefore, I need input on some inexpensive commericial brand sound reinforcement treatment to improve the focus and make the room more damped(not deadened). In addition, should acoustic panels hang behind the speakers or behind my sitting position?? I play mostly classic rock but also some big band music, and fusion jazz. I have considered moving the system to the other side where I sit; the wall is continous and allows for a bit more placement flexibility. (BTW, long axis placement is not an option) Not a an easy chore--the speakers are 80 pounds each....Nevertheless, I love these speakers, I hope they are not too big for the room space. All suggestions recommended. Jim
Have some Roomtunes installed. Start with Cornertraps in the upper corners - they made a difference in my past setups. Then experiment (now I have some Tube Traps behind
my Acuhorn to disperse the rearfiring waves). There is also
literature on the subject, as it is more science, than many
other subjects in our hobby! P.S. I have 4 unneded Corner
Traps to sell.
Jesus this is going to need work...Sunnyjim, you will need to place 4 inch thick traps behind the speakers in the corners, adjacent to the speakers on the walls, and somehow block the windows with a hanging rug or something that you can easily remove. The corners are notorious for accumulating bass, the sides of the speakers radiate first reflections onto the side walls, and the windows reflect everything that hits them. Place traps in the opposite corners of the room also. I have a 12 X 25 foot room and have the adagios also. This is exacly my setup. The rug helps, and if you can do it, put some traps on the ceiling above the speakers. Its might sound crazy...but this is a typical configuration.
You never mentioned a bass problem, which is what corner and ceiling corner treatments would address. My fave(Auralex), Applied across the wall behind your listening position, will resolve your issue(slap echo/excessive upper mids resonance), ie:( There are also lesser priced knockoffs on eBay, if you type, "acoustic foam" in the search bar. The 2" thick wedge stuff will be right for your target freqs. Find the side wall/ceiling reflection points and apply some absorption there, to tighten your sound stage and improve image focus.
Thanks for the link, Rodman. I ordered a set. Auralex SubDudes have worked well for me.