Medium size room (small office,
group therapy room, home, etc.)
Here you have a choice of PZM mics or the MB-3
mic. The PZMs are omnidirectional; the MB-3 is
unidirectional.
If the mic must be mounted in the ceiling near a wall,
and most talkers are in the middle of the room, the
MB-3 is a better choice (Fig. 2). It will pick up less
room reverberation than the PZM would in the same
location.
Figure 2
If the mic can be mounted in the ceiling near the mid-
dle of the room, and most talkers are in the middle of
the room, the PZM is the better choice (Fig. 3). It
will pick up less room reverb than the MB-3 would in
the same location.
Figure 3
Since the MB-3 is unidirectional, why doesn’t it pick
up less reverb than the omnidirectional PZM? If the
MB-3 is overhead of the talkers, it picks them up
approximately 90 degrees off axis, where its output is
reduced by 9 dB. So it picks up talkers rather
weakly, but picks up reverb strongly on-axis.
The MB-3 works best when talkers are in front of the
mic and within its 60-degree pickup angle. For
example, when the mic is near a wall and the talkers
are in the middle of the room (Fig. 2).
Police interview room or psychia-
trist office
Mount a PZM-10, PZM-11, or PZM-11LL in the
ceiling directly over the interview table (Fig. 4).
Another placement is in a wall close to the table at
mouth height. Since the mic resembles a light
switch, it does not intimidate the interviewee.
. Figure 4
If possible, deaden the room acoustics by adding cur-
tains, carpet, or acoustic-tile ceiling. This reduces
room reverb and provides a clearer sound.
