Handbook for Sound Engineers

Microphones 541

to control this situation was through the choice of
microphones having different variations of the polar
pattern versus frequency. With the DSP-4P processor,
nearly ideal directional characteristics can be selected,
and nearly any frequency-dependent directional charac-
teristic that may be desired—e.g., a cardioid becomes
omnidirectional below the midrange, so that it has better
response at the very lowest frequencies. Also modeling
a large-diaphragm microphone is possible.
Furthermore, in excessively reverberant spaces one
could record a drier sound (cardioid or supercardioid

setting) or, in spaces that are dry, accept more room

reflections (wide cardioid or omni setting) in the corre-

sponding frequency range.

In such cases it is not the frequency response but

rather the ratio of direct to reflected sound, that will be

altered. That cannot be done with an equalizer nor can a

reverb unit reduce the degree of reflected sound after

the fact.

In the arrangement of Fig. 16-107, an omnidirec-

tional microphone with a mild high-frequency emphasis

in the direct sound field is used. Because of its angle of

orientation, the capsule has ideal directional response in

the horizontal plane; the high-frequency emphasis

compensates for the high-frequency losses due to lateral

sound incidence.

A figure 8 microphone is set directly above the

omni. The direction to which it is aimed will determine

the orientation of the resulting adjustable virtual micro-

phone. The hemispherical device attached to the top of

the figure 8 flattens the response of the omnidirectional

microphone at the highest frequencies.

Figure 16-106. Hemicardioid polar pickup pattern for a

Shure AMS surface microphone. Courtesy Shure Incorpo-

rated.

Legend

150 o

120 o

90 o

60 o

30 o

0

30 o

60 o

90 o

120 o

150 o

180 o

20 dB



 dB

Legend

1000 Hz

200 Hz

5000 Hz

A. Side view

120 o

150 o

0 o^180 o

30 o

60 o

90 o

 dB



 dB



 dB

Surface plane

1000 Hz

250 Hz

500 Hz

B. Top view

 dB



 dB

20 dB

Figure 16-107. A Schoeps PolarFlex microphone with an

omnidirectional and a figure 8 microphone. Courtesy

Schoeps GmbH.