Your Room
This is an area that requires both a little background to
understand and some time and experimentation to attain
the best performance from your system.
Your room is actually a component and an important part
of your system. This component is a large variable and can
dramatically add to or subtract from a great sonic experience.
All sound is composed of waves. Each frequency has its
own wave size, with the lower, or bass frequencies liter-
ally encompassing from 10 feet to as much as 40 feet. Your
room participates in this wave experience like a swimming
pool with waves reflecting and becoming enhanced depend-
ing on the size and shape of the room and the types of
surfaces in the room.
Remember that your audio system can actually generate
all of the information required to recreate a sonic event
in time, space, and tonal balance. Acoustically, the role of
an ideal room would be to neither delete nor contribute
to that information. However, nearly every room does to
some degree.
Terminology
Standing Waves
Sound coming from a subwoofer bounces around in a
room until a pattern emerges—this is called a standing
wave. Typically, this is only a problem with frequencies
below 100Hz. When this happens different parts of your
room experience either an excess or a lack of bass.
Some people believe that having a room without parallel
walls will eliminate this effect. The truth is that non-parallel
walls only generate different standing wave patterns than
those that occur in rectangular rooms.
Usually, you can excite most of the standing waves in a
room by putting the subwoofer in a corner. Listening
position determines which standing waves you will expe-
rience. For instance, if you sit in a corner you will hear
most of the standing waves. This can be an overpowering
experience. Sitting next to a wall can also intensify the levels
of the standing waves that are experienced.
Resonant Surfaces and Objects
All of the surfaces and objects in your room are subject to
the frequencies generated by your system. Much like an
instrument, they will vibrate and "carry on" in syncopation
with the music, and may contribute in a negative way to the
sound. Ringing, boominess, and even brightness can occur
simply because surfaces and objects are "singing along" with
your speakers.
Resonant Cavities
Small alcoves or closet type areas in your room can be
chambers that create their own "standing waves" and can
drum their own "one note" sounds.
Room Acoustics 17
ROOM ACOUSTICS