Room Acoustics overkill or worse?

Unless you have dipoles or panels I would suggest you do the wall behind your listening position more than the wall behind the speakers. Doing all corners with superchunks will probably have the biggest impact....3" thickness is barely enough to do anything in the bass.

Absorption is what you are doing. Sonics will degrade if you cover with silk. So, a better bet would be to cover with speaker grille cloth. Check Parts Express for their black, 70 inch wide stuff. Inexpensive and very effective. Also, have you considered moulded form rollers that you could also cover the wall. The roundness creates better absorption. Here is a link.
http://www.performbetter.com/detail.aspx_Q_ID_E_4918_A_CategoryID_E_235
Tweak, tweak and more tweak.

I wouldn't recommend over damping the room. It all depends on the room. Today most acoustical engineers and audio setup people prefer combinations of diffusors and absorbers.

An over damped room robs a system of vital presence and energy, so go slowly.

Maybe, maybe not. I looked for your Virtual System and you have nothing posted; therefore, we have no idea if you're using dipoles, rear ported, front ported, omnis or whatever. Also, we have no idea of the room size and reflectiveness of the remaining walls.

Generally, assuming the room is otherwise relatively lively, this will not be a problem. I take it your wife wants to cover the wall with silk fabric. Normally that's done over a light batting and would not be a problem. If you start adding thick absorbing material behind the silk, then you'll really deaden the room a lot.

Of course, you should look into LEDE technology. That's live-end-dead-end. This is used in some studios and demonstration room. The speakers are at the dead end of the room. It takes a powerful bass speaker to overcome the lost bass reinforcement. If you've got low ceilings and a narrow long room and need to place the speakers on a short wall, then this can be a good solution.

Anyway, generally, so long as you don't get carried away with absorbing material behind the silk, you'll be ok and that'll be a very nice listening room. Yes, you may need to move your speakers back a little closer to the wall, but that's no big deal. Any significant room changes will demand re-setting of the speakers.

Dave

thanks for all the replies suggestions. I should have described my setup better. Sorry I have to get down to posting my system soon............

The room is 15'x12' with a sloped ceiling along the shorter wall. I have large french windows along one of the 15' walls and an 8' opening on the opposite side into a double ht. living room. The walls are 9" brick with cement plaster. The ceiling is concrete, but covered from below with pine wood slats. The floor is a hard cement mosaic floor. Typical construction in India.

The speakers consist of a pair DIY 15" subs, which are ported at the back and a pair of sealed MTM's along the shoter wall. I have have no resonance from any of the cabinets. Solid 1 1/2" MDF. I usually put a carpet on the floor. I also have a 25" TV between the speakers.

So far the foam treatment has really cleaned up and tightned the sound. The most pleasing change has been the increase in scale and body of the instruments. I wanted to put panels behind the speakers and in the corner but better half frowns at that idea.................