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Mic Placement Strategies
There’s more than one way to select and place microphones. After having
reviewed the science of microphones, bear in mind that recording is an art.
The placement of your microphones determines what your listener will
hear. There are some established conventions that achieve certain results.
We’ll look first at the basic underlying techniques, then move on to some
specific examples.
Distant and close
Any recorded sound comprises both direct and indirect or reflected sound.
Direct sound travels straight from the source to the microphone and is the
“cleanest” sound because it is unchanged from its source. Indirect sound
reflects off surfaces in the room or recording environment before reaching
the microphone; it is colored in the process and arrives with a small delay.
Just do it:
Sometimes
the best way to learn
about mic placement is
simply to try it. Set up a
microphone near a
source and begin moni-
toring the results. Be
sure to experiment with
distance and angle.
Figure 6.9 Left: A ribbon
classic: the original RCA
Type 77-DX. (Photo courtesy
Stanley O. Coutant; micro-
phone from his private
collection, www.coutant.org)
Right: AEAs R84 mic has
the looks and figure-8 polar
response of an RCA mic,
but has been updated with
a more rugged design and
improved sound. (Photo
courtesy Audio Engineering
Associates)
By using different mic placements, you can affect the mix of direct and
indirect sound. The most basic forms of microphone placement are close
and distant (or ambient):
Close miking is the use of microphones near the source, as in a vocal-
ist singing directly into a microphone or the placement of a mic directly
next to a guitar amp or kick drum. Close miking picks up mostly the
direct sound.
Distant (ambient) miking is the use of greater space between a mic and
source, such as a boundary mic onstage or a stereo mic in the audience of
an orchestral performance, and tends to pick up more reflected sound.
The blend of direct and reflected sound you want to record depends on
the result you’re trying to achieve. If you want an intimate guitar record-
ing, one that might sound as though your ear were up against the body of
the instrument, you’ll want as little reflected sound as possible. On the
other hand, if you’re recording a choir performance in a cathedral, you’ll
want to capture some reflected sound since this is a desirable quality
of the space.
Either way, excessive reflected sound can cause problems. Phase cancellation
occurs when certain partials arrive 180 degrees out-of-phase with respect
to the direct sound. Phase cancellation causes some frequencies to disap-
pear, thus creating a hollow sound. One way to compensate for this prob-
lem is to use boundary mics for distant miking (see the sidebar “Boundary
Condenser (PZM)”). Too much reflected sound can also make a record-
ing sound muddy. Solutions include employing more direct miking or
setting up acoustic barriers to prevent reflected sound from reaching
the mic.
To obtain the desired mix, many recordists use some combination of close
mics and distant mics. Even with only two microphones, this combination
will give you options when blending the two signals.
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Boundary Condenser (PZM)
Examples: Crown PZM-30D, AKG C 542 BL, Neumann GFM 132 (Figure 6.10)
Needs Power? Yes
What they are: Condenser mics with omni patterns, specially designed in a flat
housing to make use of an internal boundary plate and/or flat mounting surface
Why use them? Allows surface mounting, compensates for problems with dis-
tance recording, avoids sound coloration near surfaces, unobtrusive appearance
Best for: Distance recording (as on a stage), recording surfaces (as on a piano lid)
Boundary microphones, often called PZM (Pressure Zone Microphones) after the
trademark of their original creator Crown, are specialized condenser microphones
designed to be mounted to a solid surface like a floor, wall, or piano lid. By utilizing
the surface, they can compensate for reflected sound that would otherwise inter-
fere with the quality of a distant-miked recording. (With traditional mics, reflected
sounds and direct sounds arrive at different times, canceling out some sound.With
boundary mics, reflected and direct sound is in phase.)
Some boundary mics include bass filters, which eliminate rumble sounds. All have
an omni pattern, but of course half of the omni pattern is lost on the boundary
side of the mic.
Figure 6.10 The flat design of boundary mics like Neumann’s GFM 132
opens up placement locations that aren’t possible with other mics. (Photo
courtesy Georg Neumann GmBH)

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