Primer
Crestron
Surround Sound
of the room. If you have a single rear speaker, place it at the same
height as the surround speakers, in the center of the back wall facing
the front of the room. You should keep all of the surround speakers at
the same height to give the sound an even feel as it passes throughout
the surrounds.
Subwoofer Placement
Too much or too little bass creates an unsatisfying listening experience.
The number of subwoofers, their locations and the listener position are
extremely important to good bass. Frequencies below 120 Hz are omni-
directional, the sound radiates throughout the room and the source
cannot be localized. This works to our advantage in many rooms.
Listeners need not sit in front of the subwoofer to get good bass
response.
The location of the subwoofer is critical for the best response; the worst
place to put a subwoofer is in the middle of a room. Moving the
subwoofer closer to a wall or corner improves the overall room
response.
Locating the subwoofer in the corner of the room can often provide the
best room sound level. However, this position can also cause room
modes to be more apparent and affect the listening position. If all of
your listening positions sound good with the subwoofer in the corner,
then you are doing well. Many times though, the best position for
viewing a movie and listening to a surround system has the worst bass
response. This is due to a room mode at that position that causes a loss
of bass. The frequencies are actually canceling themselves out at that
particular position. Meanwhile, people that may be sitting in off-center
may have loud and muddy bass, because at this position, the room
mode is doubling the amplitude of the frequency that is causing the
increase of the volume. You can adjust for this situation a several ways.
First, adjust the position of the subwoofer until you have an overall
good bass response throughout the room. As you move the subwoofer,
notice that the locations with the most bass and the least bass changes.
You are moving the subwoofer through the room modes. The goal is to
find the best location to minimize the number of modes in the main
seating areas.
For middle size to larger rooms, add a second subwoofer. The proper
placement of these subwoofers together can create a great room
response without a loss at the main seating position and an increase the
response in the room corners.
Adding a second subwoofer can also remedy the room mode situation if
done properly. Do not place the subwoofers on the same lateral plane,
both subwoofers against the front wall, both subwoofers against the
back wall, or exactly opposite one another. This actually defeats the
purpose of adding a second subwoofer by increasing the room mode.
Placing a subwoofer in the front right corner and one in the back left
corner, or placing a sub up front and one on the side wall will better
cover the room modes. Start by placing the subwoofers in the corners
and gradually move them out. The best sound medium to use is pink
noise because of the range of random frequencies produced.You can
also purchase bass traps and place them through out the room in the
corners and other locations. These are commonly placed in corners
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Surround Sound
Primer – DOC. 6122
