Hiya Durf,
szitznitz (or something) now how much is feet in mtr.? mmmm 1 feet = 0.304 8 meter
soooo
15 feet = 4.572 meter
17 feet = 5.181 6 meter
7 feet = 2.133 6 meter
looks ok, not really high, that is a pity, treatment depends on the material of the walls...
try to avoid going too symmetrical and vary the surfaces to avoid a completely dead room like suggested by Anderson. I like a bit of a live sound in the CR too. You have to decide on that first. check the board
if you still need books check amazon:
http://www.amazon.com/gp/product/007...Fencoding=UTF8