Handbook for Sound Engineers

1416 Chapter 37

37.2 Personal Monitor System Advantages

The traditional, floor wedge monitor system is fraught
with problems. Performers, especially singers, find it
difficult to hear things clearly. Feedback is a constant
and annoying issue. And the monitor engineer forever
battles to keep up with the needs of the individual
performers. Anyone who has performed live has prob-
ably dealt with a poor monitor system, but even a great
system has many limitations due to the laws of physics,
and those laws bend for no one. The concept of in-ear
monitoring rose from the desire to create an onstage
listening experience that could overcome the limita-
tions imposed by a traditional floor monitor system.
Many parallels exist between personal monitors and
a traditional floor wedge setup. The purpose of any
monitor system is to allow performers to hear them-
selves. The sounds to be monitored need to be
converted to electronic signals for input to the monitor
system. This is usually accomplished via microphones,
although in the case of electronic instruments such as
keyboards and electronic drums, the signals can be
input directly to a mixing console. The various signals
are then combined at a mixer, and output to either
power amplifiers and loudspeakers or to the inputs of
personal monitor systems. Any amount of signal
processing, such as equalizers or dynamics processing
(compressors, limiters, etc.) can be added inbetween. A
hardwired personal monitor system is similar (in signal
flow terms) to a traditional wedge system, since the belt
pack is basically a power amplifier, and the earphones
are tiny loudspeakers. A wireless personal monitor
system, however, adds a few more components, specifi-
cally a transmitter and receiver, Fig. 37-3. From the
output of the mixer, the audio signal goes to a trans-
mitter, which converts it to a radio frequency (RF)
signal. A belt-pack receiver, worn by the performer,
picks up the RF signal and converts it back to an audio
signal. At this stage the audio is then amplified and
output to the earphones.
The term personal monitors is derived from several
factors, but basically revolves around the concept of
taking a monitor mix and tailoring it to each performer’s
specific needs, without affecting the performance or
listening conditions of the others. The concept is
broader than that of in-ear monitoring, which states
where the monitors are positioned, but gives no further
information on the experience.
The four most prominent benefits when using them
are:

• Improved sound quality.


• Portability.
  
  
  • Onstage mobility.
  
  
  • Personal control.
  
  
  
  

37.3 Sound Quality

There are several factors that, when taken as a whole,

result in improved sound quality with personal monitor

systems. These factors include adequate volume for the

performers, gain-before-feedback, hearing conservation,

reduced vocal strain, and less interference with the audi-

ence mix.

37.3.1 Adequate Volume

The most common request given to monitor engineers is

“Can you turn me up?” (Sometimes not phrased quite so

Figure 37-3. Two wireless personal monitor systems.

A. Sennheiser Evolution 300 series IEM.

Courtesy Sennheiser Electronic Corporation.

B. Shure PSM 700 system.

Courtesy Shure Incorporated.