Octet Matrix Audio Home Theater Speaker User Manual - page 3
Home Theater Speaker Placement
Octet Matrix Audio -2010
Page 3
Center Channel
The center channel is used to anchor the dialog to the screen from all off center listening positions, and
to work with the left and right front speakers to reproduce audio effects across the front soundstage.
The center channel speaker must be positioned in the center of the screen and as close to the top or
bottom of the screen as possible. Choose the location above or below the screen so that the center
channel design axis is as close to the front speaker design axis as possible (horizontally). Ideally, the
center channel design axis should be positioned at ear level, but this is rarely practical due to typical
screen placement heights. To compensate, tilt the center channel speaker slightly up or down so that
the design axis is pointed to ear level at the primary listening position.
Surround Speakers
The surround speakers provide the movement of images from the front to the rear, from the rear to the
front, and across the rear. Examples include bullets whizzing by and helicopters flying overhead.
Surround speakers are also frequently used to create environmental effects that make you feel like a
part of the activity, or to create a sense of space. Sports telecasts often direct sounds from the crowd to
the surround speakers to make you feel like you’re in the stadium. A very realistic perception of being
somewhere else can be obtained through the use of properly located surround speakers. Sounds like
birds chirping, leaves rustling, traffic, and rain hitting pavement are all effects that moviemakers use to
make us feel like we’re taking part in the story, not sitting in our living rooms.
While one of the primary goals of surround speakers is to realistically reproduce movement, the
implementation is different than with the front speakers. The primary reason for the difference is that in
order to create environmental effects, it is much more realistic if our hearing mechanism can’t locate
the sound source and the sound appears to be coming from multiple directions. In order to accomplish
this, surround speakers are mounted higher than ear level, and we don’t mind if nearfield reflections
occur because they actually contribute to creating a more diffuse sound field. Some home theater
installations actually fire the surround speakers towards the ceiling and rely on the reflected sound to
create the surround field rather than the using the direct sound from the speakers. Other methods used
to create a more diffuse rear sound field include the use of dipole or bipole speakers. Follow instructions
provided with the speakers for placement recommendations.
The primary listening position should be centered between the left and right surround speakers, which
should be mounted at least 2 feet above ear level, and preferably 3 feet or slightly more. The surround
speakers should be positioned somewhere between 90° and 110° relative to the plane formed between
the center of the screen and the primary listening position. The table on the following page lists the
distance between the listener’s ears and the plane formed between the centers of the surround
speakers (DS2).