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Chapter 4

Stereo Miking Techniques

The use of stereo miking techniques utilizing matched pairs can make all the difference between
mediocre and outstanding recordings. After all, we listen to the world around us in stereo via
matched pairs of ears. Stereo miking can be used in applications ranging from individual instruments
to small ensembles to full orchestras and other concert events. In this section, we ll cover some of
the proven stereo miking techniques that have been used on countless professional recordings. (For
the purposes of this guide, stereo miking techniques are a subset of multi-microphone techniques
specifically aimed at accurately capturing a sound source with a left-right balance similar to the way
our ears perceive a sound source.)

Several factors must be considered in determining the best stereo miking technique for your
specific application. Although results vary with different polar patterns, it is common to use
distance from the source to determine the amount of room reflection versus direct source signal
desired. Physical restrictions in distance or position may also come into play, such as the need to
maintain clear lines of sight from audience to stage. It is also advisable to consider mono
compatibility, especially if the resulting material will wind up on radio or television.

The following stereo miking techniques fall into two basic categories coincident and spaced.

Coincident

techniques rely on the microphones being placed in extremely close proximity to one

another, while

spaced

techniques place them further apart. While the coincident methods are

considered to be very accurate, some listeners find them to be too accurate. Common criticisms
are that the stereo field is too narrow or confined to the speakers on playback. (You can sometimes
compensate for this by moving the coincident mics slightly apart from each other in order to
introduce a time delay between sides.)

Spaced techniques are considered less accurate, yet more spacious sounding. In effect, widening the
space between mics widens the virtual placement of our ears. As with everything surrounding
microphones and their techniques, these considerations are subject to interpretation and
experimentation. In fact, it is not uncommon to find engineers employing techniques from both
categories simultaneously. In such a case, the coincident pairs provide a well-defined primary signal, while
the space pairs are placed to capture the reflected sound that provides extra control over ambience.

X-Y

The

X-Y

miking technique employs a matched pair of

microphones overlapping as much as the mic bodies allow.
As pictured, place a pair of cardioid mics as close to each
other as possible with the capsules at an angle to each
other.The mic on the left captures the right signal and vice
versa. While 90 degrees is the most common angle
between the capsules, the working range is approximately
60 to 135 degrees. The wider the angle, the wider the
perceived stereo field will be. In general, the distance from
the sound source combined with the intended stereo
spread (the width of a stage, for example) will determine
the appropriate angle.

The use of cardioid patterns means that the X-Y configuration as a whole rejects signals from the rear. (You
can also experiment with super-cardioid patterns to provide more isolation between left and right sonic
imagery.) This rear rejection has several advantages.The configuration can be moved further away from a stage
to preserve sight lines. The reduced sonic clutter is also of benefit when converting the stereo recording to
monaural. Increasing the distance between the coincident mic pair and the sound source decreases stereo

Choosing & Using Microphones

Sound Source

X-Y miking employs a matched

pair of coincident cardioids