Recording - April 2018 - 56

STUDIO 101
Let's now look at some details about
mic types, and how the application
might affect the microphone you choose
to use.

Close vs. distance miking
Close miking technique is used when
you are trying to isolate a specific
sound source. If you put a microphone
very close to a guitar amp, and if it has
a directional pickup pattern, you will
eliminate most of the sound of nearby
instruments. This is useful when multitrack recording a band, since isolating
instruments can give you a lot of flexibility
when you are mixing.
Close miking with a directional microphone is also used a lot for male spoken
word and male singers/rappers. In this
case, you are actually taking advantage
of proximity effect, which creates a
low-frequency boost considered useful
for beefing up male vocals. It's less
effective with instruments or drums, and
the proximity effect changes with the
microphone in use. However, if you are
after that "broadcast announcer" sound,
consider close-miking your voice talent.

While close-miking everything used
to be a standard procedure, this has
somewhat fallen out of favor-often
because it ends up with a very unnatural sound. Where mid-1980s recordings often featured 12- or 14-mic drum
setups, now it is common to use a 3-mic
technique that uses distance placement
to create a more natural sound. And if
you are recording ensembles (strings
or horns), you will want to embrace
distance miking, since you will get a
naturally blended sound that meets the
expectation of listeners. In a future installment, we'll go over these choices
in detail.

Phase relationships and
on/off-axis placement
One of the issues that can occur
when you are close-miking is phase
cancellation. This occurs when two
nearby microphones are getting almost
identical sounds from the same source.
Because of their different distances,
incoming sound waves captured by the
mics are out of phase with each other,
causing certain frequencies to emphasize

PART 4

Microphone Basics

or cancel each other and create a
hollow, weak overall sound.
The 3:1 Rule is a rule of thumb that
engineers use, and it states that if close
mics are being used for recording, two
mics should be three times farther apart
from one another than the distance from
each mic to the source it's capturing.
This trick doesn't always work, but it's
good to remember when miking up
instruments in tight quarters.
While we're talking about mic placement, let's also talk about on-axis and
off-axis placement. On-axis placement
has the capsule or diaphragm of the
microphone pointed directly at the sound
source, while off-axis placement is when
the mic is at an angle to the source.
You might find yourself tempted to tilt
a microphone to position outside sound
sources in the null of its pickup pattern.
However, as we mentioned before, the
frequency response of a directional mic
varies as you move the source off-axis-
and not always in a predictable way.
While this technique can produce good
results, use care when employing off-axis
positioning, as it can also make a great
mic sound awful!

What is our mic capturing?

Figure 2. Polar pattern of a cardioid mic at
different frequencies. This variation is common to nearly all mics.
56

RECORDING April 2018

All this discussion about how microphones operate (and some standard
use cases) can fall flat if the sound of
the room doesn't work. One of the
hallmarks of a great engineer is that
the first concern isn't the gear in the
control room-it is the sound of the
band in the studio. If the actual sound
isn't right, it can be brutal trying to
extract a good-sounding mix.
The first thing to consider is what
sound your microphone is actually
picking up. Are you getting only the
direct sound of a snare drum, or is its
sound being reflected off a nearby
wall? Does the guitar amp sound better
if you are standing six feet away-and
therefore, would that be a good place
for a microphone? Striving for a great

Table of Contents for the Digital Edition of Recording - April 2018