Handbook for Sound Engineers

1430 Chapter 37

the chance for feedback. Eliminating the floor monitor
also eliminates the worst possible feedback loop. With
the “loudspeakers” sealed inside the ear canal, there is
no chance for the signal to reenter the microphone. No
equalizer or feedback reducer will ever be as effective as
personal monitors at eliminating feedback on the stage.

Many other uses are possible for personal monitors.
Choir directors could use them for cues, or to hear the
pastor more clearly. Pastors who desire monitor rein-
forcement of their speech microphones, a sure-fire
recipe for feedback, will find this a much better solu-
tion. Organists located at the rear of the sanctuary could
use them to better hear the choir located up front, or
also to receive cues. The advantages extend well
beyond the benefits to the performer, and increase the
overall quality of the service and the worship
experience.

37.8 Expanding the Personal Monitor System

37.8.1 Personal Monitor Mixers

Personal monitoring gives the performer an unprece-
dented level of control. But for the performer who
desires more than simple volume and pan operation, an
additional mixer may be implemented. Personal monitor
mixers are especially useful for bands who have a
limited number of available monitor mixes, or who do
not have a monitor engineer, or anyone at all to run
sound. In a perfect world, all performers would be
happy listening to the exact same mix; in reality,
everyone may want to hear something different. A small
mixer located near the performers allows them to
customize their mix to hear exactly what they desire.
Theoretically, any mixer can double as a personal
monitor mixer, but most lack one key feature; the input
signals need to find their way to the main (FOH) mixer
somehow. Large sound systems with separate monitor
consoles use transformer-isolated splitters to send the
signals to two places, but these are prohibitively expen-
sive for most working bands and small clubs. Y-cables
can be used to split microphone signals, but they can get
messy and are somewhat unreliable. A few manufac-
turers produce mixers with integrated microphone split-
ters. These range from basic four channel mixers with
only volume and pan controls for creating a single mix
to larger monitor consoles that can provide four or more
stereo mixes along with fader control and parametric
equalization.

37.8.2 Distributed Mixing

Distributed mixing is the direct result of advances in the

area of digital audio networking. By converting analog

audio signals to digital, audio can be routed to many

locations without degradation or appreciable signal loss.

Unlike with analog personal mixers, cabling is far

simpler. Typically, analog outputs from a mixing

console connect to an analog-to-digital converter.

Multiple channels of digital audio can then be routed

from the A/D converter to personal mixing stations

located by each performer, using a single common

Ethernet (Cat-5) cable, thus eliminating a rat’s nest of

microphone cables or the large, unwieldy cable snakes

required for analog audio distribution. Cat-5 cable is

inexpensive and readily available. The mixing station

provides an analog headphone output that can drive a

set of isolating earphones directly, or better yet, connect

to either a hardwired or wireless personal monitor

system. If nothing else, the personal monitor system

offers the advantage of a limiter for some degree of

hearing protection, as well as a volume control at the

performer’s hip. The mixers supplied with most distrib-

uted systems do not always have a limiter. Most systems

provide eight or sixteen channels of audio, allowing

each performer to create his or her own custom mix,

independent of other performers and without the inter-

vention of a sound engineer. Note that giving this level

of control to the performers will probably require some

training in the basics of mixing to be successful (see

Creating a Basic Monitor Mix above).

37.8.3 Supplementary Equipment

In-ear monitoring is a different auditory experience

from traditional stage monitoring. Since your ears are

isolated from any ambient sound, the perception of the

performance environment changes. There are several

other types of audio products that can be added to a

personal monitor system to enhance the experience, or

try to simulate a more “live” feel.

37.8.3.1 Drum Throne Shakers

Something performers may miss when making the tran-

sition to personal monitors are the physical vibrations

created by amplified low-frequency sounds. Drummers

and bass players are particularly sensitive to this effect.

Although using a dual driver earphone usually results in

more perceived bass, an earphone cannot replicate the

physical sensation of air moving (sound) anywhere but

in the ear canal. Drum shakers exist not to provide