[Cheeseboy]

Big Headache is right.  His room sucks canal water.  He is so close yet so far from maximum sound quality. 

In order to get the maximum SQ out of a room like that IMHO I would add another couch and go for stadium seating.  The more people, drinks and popcorn in a room, the better it sounds.   I would consider a bar in the back with a Helmholtz Bass trap built in.

You're gonna have alot of fun in that room.

[Glenn Kuras]

I have discovered that my slap echo is audible from my listening position if I clap loud enough.

Slap echo is dependent on where the speakers are located and where you sit. If you want to find the spot that is effecting your seating spot then play a short clap through your speakers and listen from your seating location. If you just sit and clap your hands it will not give you the proper indication where the "slap echo" is coming from.

Glenn
GIK Acoustics

[bernardo]

Glenn-
I know your intentions are good but I don't have nor do I have a way to make a recording of hands slapping to play thru my speakers. If you know of a recording that is available let me know. FWIW the slap echo sounds like it comes from the same place when clapping my hands from my seat, at the speakers, or most any location between the speakers and the wall behind the speakers. It sounds to me like it is echoing at the wall/ceiling joint in the two corners behind the speakers. That is where I would start with treatment. Keep in mind I have a large cavernous cathedral ceiling - 360 square feet varying from 9 feet high at the short walls up to 14 feet high at the center of the room.

[Glenn Kuras]

I just googled and found this one.. I wish it was recorded in more of a dead room, so you might be able to find a better one.

http://free-loops.com/6795-hand-clap.html

Also something like a snare hit would work.. Just let google be your friend. 

One other idea is sit in your seat and have someone clap over the speaker.

[bpape]

That's kind of the whole problem is that when YOU clap, your ears and the source of the sound are in the same place - which is not how you listen - where the source of the sound is where your speakers are and your ear is somewhere completely different. 

Bryan

[bernardo]

Bryan-
A few posts back you stated "You don't need to cover all of the wall surface. Just a reasonable amount space out high around the perimeter can do wonders." This is the other issue which has me guessing about where to try the treatment. At what point would you install a row of several 2x2 panels for instance? At an angle following the wall/ceiling joint up to the ceiling high point or just pick a point say 10 feet above the floor and install them in a row horizontally?

[Alex Reynolds]

30% seems a little high, but I suppose it might be necessary in some cases. Blankets and foam will do similar things - they both absorb the high end and not much below hi-mids. I would try it with blankets first to see how you like it. Foam will look a bit better but give similar results.

[Alex Reynolds]

Bryan-
A few posts back you stated "You don't need to cover all of the wall surface. Just a reasonable amount space out high around the perimeter can do wonders." This is the other issue which has me guessing about where to try the treatment. At what point would you install a row of several 2x2 panels for instance? At an angle following the wall/ceiling joint up to the ceiling high point or just pick a point say 10 feet above the floor and install them in a row horizontally?

It really shouldn't matter. Flutter echo happens between two parallel (or very close to parallel) hard surfaces. If there is anything in the way, it will break up flutter echo. Think of it as light between two mirrors on parallel walls, where you get that weird tunnel effect. Put something in the way of one of the mirrors and you won't see a tunnel at that spot. Completely cover a mirror and no more tunnel. Sound works the same way between parallel walls.

Usually, the "upper" side of the room is suggested since there are likely objects in the lower portion of the room, meaning not nearly as much flutter echo down there. So the most bang for your buck would be above or to the side of where objects are covering the wall surfaces. Hopefully that makes sense!