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How to reduce phase cancellations from surface
reflections:
Sometimes you must place a microphone near a
hard reflective surface. Situations where this might
occur are reinforcing drama, musicals, or opera with
the microphone near the stage floor, recording a
piano with the mic near the raised lid, or recording
an instrument surrounded by reflective baffles.
This situation can cause phase cancellations which
give a strange tone quality. Solve the problem by
using a Crown PZM or PCC microphone taped to
the piano lid, wall, floor, table, or other large flat
surface.
How to reduce handling noise and thumps
•
Use an omnidirectional microphone, such as a
GLM-100 or any PZM.
•
Use a directional microphone with low sensitivity
to handling noise and thump, such as the CM-200A,
CM-310A, PCC-160, PCC-170, or PCC-200.
•
Use a directional microphone with an internal shock
mount.
•Use a shock-mount stand adapter, either handheld
or on a mic stand an example is the CM-SM.
•
Place the mic stand on foam or sponges.
How to reduce lavalier clothing noise
•
Tape the cable to clothing.
•
Strain-relieve the cable by using a belt clip.
•
Use an omni-directional lavalier (GLM-100) rather
than a uni-directional lavalier (GLM-200). The omni
type has less pickup of mechanical vibration.
How to reduce proximity effect:
Proximity effect is the bass boost you hear when
you mike close with a single-D directional micro-
phone. “Single-D” means that the microphone has
a single distance from its front sound entry to the
rear sound entry. The close the mic is to the sound
source, the more bass you hear. To reduce proxim-
ity effect:
•
Use an omnidirectional microphone such as a
Crown GLM-100 or PZM.
•
Use a unidirectional microphone, but turn down
the excess bass with your mixer’s EQ.
•
Use a variable-D unidirectional microphone.
How to reduce pop
Pop
: is an explosive breath sound produced by the
letters “p,” “b,” or “t.” When a person says words
containing these sounds, a turbulent puff of air is
forced from the mouth. This air puff hits the micro-
phone and makes a thump or little explosion called
a “pop.”
To reduce pop:
•
Use an omnidirectional microphone, such as a
Crown PZM.
•
Use a microphone with a built-in pop filter or ball-
shaped grille, such as the Crown CM-200A or CM-
310A.
•
Place an external foam pop filter on the micro-
phone.
•
Roll off low frequencies below 100 Hz.
•Place the microphone out of the path of pop travel
— above, below, or to the side of the mouth.
For example, Figure 19 shows an interview with the
microphone placed midway between the two people,
below their mouths. Figure 20 shows how a studio
announcer can be miked to prevent pop. The mi-
crophone is at eye level so that pops shoot under
the microphone and miss it. A hoop-type pop filter
also works quite well.
Fig. 19 – Reducing pop during an interveiw.
Fig. 20 – Miking a studio announcer to prevent
breath pops.
