Figure 14-19.—Microphone polar patterns.
POLAR PATTERNS
The pickup, or polar pattern, of a microphone is the
shape of the area around it where it picks up sounds with
maximum fidelity and volume. Nearly all microphones
can pick up sounds from areas outside the ideal pattern,
but their quality is not as good. For best results, the
sound source should be within the pickup pattern,
generating enough volume to allow the audio switcher
to keep the volume control pot at a minimal level.
Microphones are classified according to the
following three basic polar patterns:
l Unidirectional
l Omnidirectional
l Bidirectional
Unidirectional
The unidirectional microphone picks up sound from
only one direction. Because of this characteristic, the
unidirectional microphone is used most frequently for
television work. It is used by aiming it in the direction
of the sound source being recorded. One advantage to
the unidirectional microphone is its ability to reject
unwanted sounds at the side and rear of the direction the
microphone is aimed.
Omnidirectional
The omnidirectional (or nondirectional) micro-
phone is live in all directions. This type of microphone
has sensitivity characteristics in which sound is picked
up in a 360-degree radius. The use of this microphone
in television production is limited; however, in certain
situations, you may use it to create a specific sound
presence. One example is recording crowd noise for a
sports production.
Bidirectional
As the name implies, the bidirectional microphone
picks up sound in two directions. This type of
microphone is used primarily in the broadcast or
recording studio. It is also used for critical sound
reinforcement applications in which front and rear
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