Read this related to SBIR, http://gikacoustics.com/speaker-boundary-interference-response-sbir/
SBIR (Speaker Boundary Interference Response) – This is a term to describe how the proximity of a speaker to a hard boundary (wall/ceiling/floor) will change the response, especially in the low end.
This is something that not a lot of people understand nor consider when planning a room.
Generally, your best off if the distance from speaker face to front wall, driver centers to side wall, and driver center to floor are 3 different dimensions in order to not reinforce any specific set of harmonics by having all the boundaries generate the same SBIR effect.
want to read more on SBIR, good links in hereGoogle SBIR results
I have Paradigm Monitor 9 floor standing speakers, they have dual tuned bass ports in the rear of them.
I've found via measurements the "best" - or optimized - location is just a few inches from the front wall.
One factor is SBIR, hence I post that info above.
For me, my driver "acoustic center" and room layout and speaker location dictated that.
I've spent more than a few hours listening, measuring, moving them, then "rinse-n-repeat" the cycle.Edited by mtbdudex - 9/21/13 at 3:35am