Hi Wayne,
See diagram for room layout. The room is a concrete block garage. Red wedges in the corners are proposed sites for bass traps. White blocks denote shelving (which could be moved). Ceiling height is 2.4m (8'). At the moment I have the sub in the top right corner (not lower down as illustrated). Sub is a dual passive so obviously one
PR facing the wall when in corner.
Moving the sub around seems to effect the peak at 24hz very little. However, bringing the sub down either the front or right side walls makes the 32hz dip even lower and also creates bigger variations, especially dips, in the higher 55-80hz range.
LP is about 1-1.5' closer to the middle of the room than the 38% from rear wall mark. Moving the seating further back increases the peak around 24hz somewhat. It also increases the big 32hz dip while moving it up to around 40hz. Centering the listening position (as shown in diagram) increases the 32hz dip dramatically - at present I'm 6" right of centre of the two lower side walls (moving 6" left of centre also reduce the dip).
Overall, the LP seems to effect the large dip at 32hz more than the sub placement.
I must admit that I have not tried moving to, and measuring from, a LP in front of the car. This is because it would necessitate moving the projector and screen, rotating the entire setup 90 deg. to face the top right side wall. What do you think, could the sound be better that way?
Cheers,
Blue