Niles Audio CM8MP - Manual (Page 5)

move the speaker farther away from the
listener, both the reflected and the direct
sound will dissipate, requiring more
power from your surround sound amplifier
channels. If the surround sound system
you are using has a small five or ten watt
amplifier for the rear speakers, stay within
five to eight feet of the listening location. If
you are using a 25 to 50 watt amplifier
you can mount the speakers 10 to 15 feet
away from the listening location and still
achieve reasonably high volume levels.
In large or unusually shaped rooms, using
multiple speakers might be the only way to
achieve a good effect. If you like to listen
to music surround modes which emulate
concert hall acoustics, more than two sur-
round speakers will prove extraordinarily
effective (See Figure 6). With Niles MP
Multipurpose loudspeakers it is easy to add
another pair without affecting the decor of
the room. However, you will need to use a
much more powerful amplifier than that
which is built into a typical surround
sound receiver or amplifier. Niles makes a
number of Systems Integration Amplifiers
with proprietary features that make them
uniquely suited to enhance a good sur-
round sound system. Consult your local
Niles dealer for more information.
The Boundary Effect
Corners can affect the bass response of the
speaker powerfully! This is called the
boundary effect. You will emphasize par-
ticular bass frequencies and cancel out
other bass frequencies when you place
speakers close to the wall/ceiling bound-
ary or a corner wall boundary. This can
make the speaker sound excessively
boomy and inaccurate to some listeners,
while to others it just seems like more bass
sound. A good rule of thumb is if you
always listen to your current pair of speak-
ers with the bass turned up, you’ll enjoy
corner placement. If you keep your tone
controls at neutral, try to keep the speak-
ers at least two or three feet from the
boundaries of the room.
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Figure 5
Varying Listening Position
Figure 6
Surround Sound
Placement for Varying
Listening Positions
If you want the freedom to sit anywhere in
a room facing any direction, and/or find
that you prefer the “all around you” sound
of some car stereos to a conventional
“sound stage” facing you, consider the
speaker placement techniques profession-
al installers use in restaurants and bars.
They place speakers in an array around
the listening area, so that the music is
always surrounding you, regardless of the
direction you face.
The rule of thumb is to add one pair of
speakers for every 100 to 200 square feet
of listening area. Curiously, this is not so
that you can play the music louder, but so
that you can play it softer! When you
have only one pair of speakers in a large
room you will notice that when the sound
is perfect in one part of the room, it is too
loud near the speakers. By placing more
than one pair in the room you will avoid
these “hot spots” of loud sound and you
will create more sonic ambiance while
maintaining clarity and a rich sound
everywhere (See Figure 5).
You can make listener position still less
critical by using mono rather than stereo.
This can be difficult to achieve with nor-
mal stereo amplifiers. However, Niles
manufactures Systems Integration
Amplifiers
® which enable one room to be
wired in stereo while other rooms are
wired in mono! Consult your local Niles
dealer for more information.
In smaller rooms or rooms that are infre-
quently used, you typically can’t justify the
expense of more than two speakers. Try to
bracket the room with the two speakers.
Diagonal placement is a very effective way
to stretch the coverage pattern of two
speakers. You can also compromise
between direct sound (for detail and clari-
ty) and reflected sound (the ambient or “all
around you” effect). The speakers can be
placed near corners to create more reflect-
ed sound. By directing the tweeters to
point away from the listener, so they create
as much reflected sound as possible, you
emphasize the ambient effect. The more
reflected sound there is in the room the
stronger the ambient effect at low volumes.
You should use moderation, however, oth-
erwise the compromise becomes too one
sided and at high volumes, the sound will
be blurred and less distinct.
Placement for Home Theater
Rear Applications
In a home theater, the goal is to reproduce
the experience of a great movie theater in
our homes. The biggest difference between
the two is the rear or surround speaker
array in a commercial theater. Here, it is
not uncommon to see twenty or thirty
speakers around the audience. This huge
array of speakers assures that you will feel
completely surrounded by the ambient
soundtrack of the movie. Film makers try
to use the “surround” soundtrack to enve-
lope you in the environment on screen.
They will place background music, rain
sounds, traffic noise, etc. on the “surround”
soundtrack. In a home with a single pair of
speakers it is easy for the jungle sounds to
sound like they are “in the middle of your
head” just like headphones!
A single pair of MP Multipurpose
Loudspeakers, properly placed, can create
a very convincing simulation of an array
of speakers. If you place them near a hard
reflecting surface you can make one pair
of speakers sound like several. Create as
many reflections as possible by placing
the speakers near a corner so that the
adjoining walls will act as a powerful
reflector. Direct the tweeters so that sound
is pointed away form the listener creating
still more reflections and thus more “sur-
round sound” effect. However, as you
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