Specifications

Hand-held Speech Microphone
The desired sound source, for a hand-held micro-
phone, is a speaking voice. Undesired sounds may include
loudspeakers, other talkers, ventilation noise, and other
various ambient sounds.
Suitable microphone performance for this application
can be provided by dynamics or condensers. Due to
frequent handling and the potential for rough treatment,
dynamic microphones are most often used, though
durable condensers are also available. The preferred
frequency response is shaped with a presence rise for
intelligibility and low roll-off for control of proximity effect
and handling noise. These microphones are typically
unidirectional. A cardioid pattern is most common,
while supercardioid and
hypercardioid types may be
used in difficult noise or
feedback situations.
Balanced low-imped-
ance output configuration is
standard while sensitivity
may be moderate-to-low
due to the higher levels from
close-up vocal sources.
Finally, the physical design is
optimized for comfortable
hand-held use, and gener-
ally includes an integral
windscreen/pop filter and
an internal shock mount.
An on-off switch may be
desirable in some situations.
Placement of hand-held microphones at a distance of
four to twelve inches from the mouth, aimed towards it, will
give good pickup of the voice, relative to other sources.
In addition, locating the microphone slightly off-center, but
angled inward, will reduce breath noise.
With high levels of unwanted ambient noise, it may be
necessary to hold the microphone closer. If the distance
is very short, especially less than four inches, proximity
effect will greatly increase the low frequency response.
Though this may be desirable for many voices, a low
frequency roll-off may be needed to avoid a “boomy” or
“muddy” sound. Additional pop filtering may also be
required for very close use.
Use of rugged, flexible cables with reliable connectors
is an absolute necessity with hand-held microphones. A stand
or holder should also be provided if it is desirable to use the
microphone hands-free. Finally, the correct phantom power
should be provided if a condenser microphone is used.
Lavalier
The desired sound source, for a lavalier microphone,
is a speaking voice. Undesired sources include other
talkers, clothing or “movement” noise, ambient sound, and
loudspeakers.
A condenser lavalier microphone will give excellent
performance in a very small package, though a dynamic
may be used if phantom power is not available or if the size
is not critical. Lavalier microphones have a specially
shaped frequency response to compensate for off-axis
placement (loss of
high frequencies),
and sometimes for
chest resonance
(boost of middle
frequencies).
The most common
polar pattern is
omnidirectional,
though unidirec-
tional types may
be used to control
excessive ambient
noise or severe
feedback problems.
However, unidirec-
tional types have
inherently greater
sensitivity to breath
and handling noise.
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MEETING FACILITIES
Audio Systems Guide for
Handheld mic
Good technique for hand-held
microphone use includes:
• Do hold microphone at proper distance for
balanced sound.
• Do aim microphone toward mouth and away
from other sounds.
• Do use low frequency roll-off to control
proximity effect.
• Do use pop filter to control breath noise.
• Don’t create noise by excessive handling.
• Do control loudness with voice rather than
moving microphone.
Lavalier mic