Initial Speaker Placement           
Please note that the following is for a basic rectangular room.

Start by determining the distance of the front wall (wall behind speakers) to the front panel of the speakers. This distance will be at the center of the front panel. To determine the distance, multiply the ceiling height by .618. Example: ceiling height is 9 feet, thus 9 x .618 = 5.56 ft. (or 66.7 inches) This is also the distance your seating position should be from the back wall (wall behind your seat).

Now determine the distance of the speaker to the side walls. Divide the room width (the wall behind speakers) in feet by 18 and multiply by 5. So, if the room is 15 ft. wide we have: 15 divided by 18 = .83.  .83 x 5 = 4.16 ft.
The center of the speakers should be about 50 inches from the side walls (4.16 x 12).

At this position, start with the speakers toed slightly towards you. Listen for awhile to get used to the sound. Play a simple recording containing a vocalist. Listen for a solid center image. Add "toe in" until the image is dead center between the speakers. Now "toe out" the speakers as far as possible without losing the center image.

You must strike a balance of image, soundstage, and tonality. If the walls to the side of the speakers are very reflective, try damping them. I have found that in most cases however that defusion is better than damping. Be careful not to damp the room heavily. This will only suck the life and impact out of the music. This is probably the most common mistake. Remember that small changes in speaker movement can make or break a set-up. Use a tape measure and make sure both speakers are equal in position as possible. You might want to try tilting the speakers backward/forward also. This can be very effective.