Here is some food for thought,before speaker placement issues,note that your dimension of 15x21x9 have a commom denominator of 3,meaning all dimensions are divisable by 3.When this occurs(all dimension having the same common denominator) there is a chance of peaks(boosts) and vallies(suckouts)at certain frequencies do to the room dimension excessively renforcing each other.Is it possible to stretch the room to 16x23x9 ? I would contact Audiogon member RIVES,and run it by him.I may be overracting,but an ounce of pervantion is worth a pound of cure.
Good Luck
Dave
davehrab
Good Luck
Dave
davehrab