Nasty slap echo

The echo you hear when clapping your hands is harmful to the sound. This can be cured with room treatment, furniture, window treatment, etc. It is best if you can cure the problem with furniture and window treatment. Whenever you add one of these items to the room continue to walk around the room clapping your hands until the room settles down. Be careful not to over do it. Too much can be worse than too little.

I just looked at the picture of your room and I see why you have echo. The dropped crown molding is the least of your worries. ASC makes some absorbing panels that would work for the side walls. I would also try throwing some blankets over the leather chairs. Leather is a reflective surface that will cause additional problems.

Josefm, This is why I always caution on using too much room treatment.

Streetdaddy, Instead of clapping at the speaker locations you should be clapping where you listen from. If you want to make this simple put your system on the long wall and you will only need to treat the wall behind your head. Unfortunately you will have to sit beside each other like normal people, but you will have a broader sound stage and you won't have to worry about side walls. You will get a bigger sound stage, better midbass, less room interaction, less room treatment required and you get to sit next to your wife.

Grannyring, Is leather a reflective surface or not? Listen with your head against the back of your leather chair then place a blanket over the chair and listen again. If you can't hear the difference then I guess it is a non-issue for you, but I can tell you it is an issue for me. It has the same effect as having your chair close the back wall only milder. If you don't want to go through the trouble of getting up to get a blanket just lean forward a little and tell me if the sound doesn't clear up a little.