Specifications

The use of audience microphones is normally
exclusively for recording, broadcast, and other isolated
destinations. It is almost never intended to be mixed into
the sound system for local reinforcement. If it is desired to
loudly reinforce an individual member of the audience, it
can only be done successfully with an individual
microphone placed amid the meeting participants:
a stand-mounted type that the member can approach or
a hand-held type (wired or wireless) that can be passed to
the member.
Non-Meeting Applications
Today, the life of meeting facilities extends far beyond
just meetings, to include classes, plays, and social events.
Sound systems can play an important role in all of these
situations. While it is not possible to detail microphone
techniques for every application, a few examples will show
how to use some of the ideas already presented.
Though most classrooms are not large enough to
require the use of a sound system, it is sometimes
necessary to record a class, or to hold a very large class in
an auditorium. In these cases, it is suggested that the
teacher wear a wireless lavalier microphone to allow
freedom of movement and to maintain consistent sound
quality. If it is desired to pick up the responses of students,
it is possible to use area microphones in a recording
application, but not with a sound system. A better technique
is for questions to be presented at a fixed stand microphone,
or to pass a wireless microphone to the student.
Microphone use for plays and other theatrical events
involves both individual and area coverage. Professional
productions usually employ wireless microphones for all
the principal actors. This requires a complete system
(microphone, transmitter, receiver) for each person, and
the frequencies must be selected so that all systems will
work together without interference. While it is possible to
purchase or rent a large number of wireless systems, it is
often more economical to combine just a few wireless
systems with area microphones for the rest of the players.
Use unidirectional boundary microphones for “downstage”
(front) pickup, and use unidirectional hanging micro-
phones for “upstage” (rear) pickup. Always use a center
microphone, because most stage action occurs at center
stage. Use flanking microphones to cover side areas but
observe the 3-to-1 rule and avoid overlapping coverage.
Turn up microphones only as needed.
Social events, such as dances, generally require only
public address coverage. Use unidirectional, hand-held or
stand mounted microphones. Dynamic types are excellent
choices, because of their rugged design. The microphone
should be equipped with an on-off switch if it is not possible
to turn down the microphone channel on the sound system.
In any case, turn up the microphone(s) only as needed.
Outdoor use of microphones is, in some ways, less
difficult than indoor. Sound outdoors is not reflected by
walls and ceilings so that reverberation is not present.
Without reflected sound, the potential for feedback is also
reduced. However, the elements of nature must be
considered: wind, sun, and rain. Because of these factors,
dynamic types are most often used, especially in the
likelihood of rain. In any case, adequate windscreens are
a must. Microphone principles are the same outdoors,
so unidirectional patterns are still preferred. Finally,
because of frequent long cable runs outdoors, balanced
low-impedance models are required.
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MEETING FACILITIES
Audio Systems Guide for
Good technique for use of audience
microphones includes:
• Do place the microphones properly.
• Do use minimum the number of
microphones.
• Do turn down unused microphones.
• Don’t attempt to “over-amplify” the audience.
• Do speak in a strong and natural voice
Tokyo City Hall