Do your sofa cushions contain Kapok, or a natural wool material? Acoustical experiments performed at Helsink Univeristy Research labs indicate that if a room is of a certain cubic dimension, and there is a glass area of less than 200 ft2, then the speakers should be placed........
There is no one magic formula for determining where, or how. The most complete answer I have ever heard, can from a respected designer of soem of the world's best audio gear - He said " It depends. How did it sound when you listened to it?"
This is the real key, and nobody can tell you how something will sound based on the building materials, furnishings, etc. You really need to set it up, see how it sounds. If it sounds not quite right (actually pleasing to you), then adjust it.
Regards,
BBIBH
