make the mistake of taking too casual an approach to the installation of the speakers in a home
theatre system. In fact, in many ways, the setup of the speakers ina home theatre is more
critical than for stereo. Even though the S-150P is less influenced by the room environment than
most other speakers, the time you spend in carefully installing yours will significantly enhance
your enjoyment of these speakers.
The LEFT, CENTER, and RIGHT speakers should ideally all be at the same height as the
viewing screen. Because the CENTER channel speaker cannot cover the screen, it will have to
be above or below the screen. Try to set up all three speakers at the same height. If this s not
practical, set them up so that they are aimed directly at the listening position.Your speakers have
great flexibility when used in combination with M&K stands or mounting brackets.
If the speakers are located behind an acoustically transparent picture screen, it is
recommended by THX that they be placed 5/8 the height of the picture screen. Placing the
speakers in this manner will ensure that sound elements relate best to the image. When
behind a transparent screen, the speakers should be angled slightly so that the front baffles are
not parallel to the screen. This will optimize the sound quality. The front speakers should be a
equal heigh, or ideally no more than 2 feet difference.
The LEFT and RIGHT speakers should be oriented with the tweeters stacked vertically and
mounted towards the outside. The S-150P should be placed in such a way as to minimize
boundary interference. For the best low frequency match between speakers we recommend the
speakers be placed a minimum of 3 feet (or 1 meter) in from of any wall. If the S-150P is placed
inside a cabinet, resonances from the cabinet cavities should be eliminated; a combination of
front baffling, internal dampening, and perforation of the sides and rear of the cabinetry should
reduce the resonance effects.
For additional information regarding speaker placement, see the THX Installation Manual
from Lucasfilm THX.
9. Satellite / Subwoofer Phasing Test
In any system using a subwoofer separate from Satellite speakers, a phasing test must be
performed to insure good bass blending. This test insures optimum sound in the critical bass
frequencies where your Subwoofer and Satellite speakers overlap.
HOME THX AUDIO SYSTEM
For a Home THX Audio system, follow the system instructions provided with the THX
controller, as you will need to have correct phase among all the speakers in the system. These
instructions will take you through the front channels, surround channels, and subwoofer.
SATELLITE/SUBWOOFER SYSTEM
If you own an M&K THX Powered Subwoofer, see its owner's manual for the correct
procedure for matching phase between the Satellites and Subwoofer. Its "SUBWOOFER
PHASE" switch makes this important test very easy. If your subwoofer does not have a
"SUBWOOFER PHASE" switch, follow this procedure:
S-150P THX Manual