What is a Stage Monitor System?

The stage monitor system is a specialized
sound reinforcement system
that operates independently of the
house sound system. Like the house
system, it consists of a console, equalizers
(and, occasionally, other signal
processors), power amplifiers and
loudspeakers. Since the monitor
system is used to help the musicians
onstage hear their performance, the
loudspeakers are pointed toward the
stage rather than into the house.
The primary difference is that the
monitor console has many separate
output channels, each driving a separate
amplifier and loudspeaker chain
with a different mix, whereas house
sound systems are monophonic or
stereophonic (even if they do use a split
stack up front and a few surround or
fill speakers, many systems are mono).
Each monitor output mix is assigned
to one or a few of the performers, and
the mix that each hears is tailored to
his or her particular needs. In order to
stay on key and on cue, for example,
the lead vocalist needs mostly to hear
the background vocalists, along with
perhaps a bit of the keyboard and
guitar. Similarly, the bass player needs
to hear the kick drum, and the drummer
needs to hear the bass. The guitar
player needs to hear both, while the
keyboardist might need to hear the
lead vocal and the guitar.
For this reason, monitor mixing
consoles usually have eight or more
output busses, and are designed for
flexibility in assigning the inputs

STAGE MONiTOR MixiNG CONsoLES

Stage monitoring systems are one of
the important keys to a successful
show. Sound reinforcement practice
has evolved to the point where even
small music clubs usually have some
type of monitoring system, and largescale
concert monitor systems can be
very elaborate. Despite their widespread
use monitor.systems are ~he
subject of a lot of misunderstanding particularly
among musicians, who are
the very ones to benefit most from a
good monitor system.

INTERfACE WiTH Sub-MixERS

Larger mixing consoles, and
sometimes smaller mixers, often have
sub input, link or expander connections.
Such connections generally apply
line level signals directly to the main
program mixing busses, and sometimes
are also provided for auxiliary busses
(echo/effects, cue, etc.). They are
intended to permit another mixer or
mixing console to be electronically
joined so that both units' inputs can be
combined onto the same busses, and
controlled with one set of master
faders. For convenient reference, the
main mixing console may be called the
master, and the sub-mixer the slave in
such setups.
The concept of sub-mixing is not
new, and it continues to offer benefits
in a number of situations. No matter
how large and complex a mixing
console, it seems that there are times
when just a few more inputs would be
helpful for a particular job, and this is
where the sub-mixer (or subsidiary
mixing console) is ideal. For example,
it may not be economical, or the
physical space may not be available, to
install a larger console to handle the
occasional need for a few additional
input channels. Sometimes the submixer
can be used to mix a separate
stage act, or to mix only the electronic
keyboards, which provides local control
for the person concerned with that
group of inputs. Then these pre-mixed
inputs are fed to the main mixing
console for distribution to the sound
system amps and loudspeakers. It may
be that a rental sound company wishes
to keep maximum flexibility in their
inventory, and would prefer to stock
two 16-channel consoles, which can go
out on separate jobs sometimes, and be
linked to create one 32-channel console
on occasion, rather than carry a single
32-channel console that can only be
used for one job at a time.
The sub-mixer inputs on a console
are generally specified to accept one of
a few standard line levels, typically
-20 dBu (78 mY), -10 dBV (316 mY), or
+4 dBu (1.23 V) nominal. In most cases
there are no input level controls on the
sub-inputs, so those levels must be
controlled by the master faders on the
sub-mixer. So long as the impedances
and levels are in the right range,

PREAMplifiERS, SMAll MixERS, & MixiNG CONsoLES

What do you do if your power amp
doesn't have an input control pot?
Lower the level of everything on the
console -INPUT GAIN, SUBMASTERS,
and MASTERS-until you have
a suitable output level. To retain
adequate fader control travel on the
submasters and masters, turn down
the input GAIN as much as practical
before resorting to pads or running all
the input faders down too far. In short,
don't take all the level reduction you
need just from the masters. Spread it
out.