process, combine, and route them to broadcast,
recording, or other destinations in a facility.
▶ The differences between a mixer and a console are that a
mixer is small, highly portable, and performs limited processing
functions, whereas a console is larger and performs
numerous processing functions. In most modern consoles,
these functions are computer-assisted.
▶ The term mixer is often used synonymously with console.
Some mixers include additional features that are found on
consoles, and some small- and medium-format consoles
have limited features that could classify them as large
▶ Consoles today are available in various configurations,
production purposes. A console may be analog or digital;
appropriate for on-air broadcast, production, or postproduction;
software-based and used as a virtual console with
a hard-disk recorder; or it may be a control surface.
▶ Regardless of their design, purpose, and complexity, consoles
have at least the three basic control sections: input,
output, and monitor. Many consoles have an additional
master control section.
▶ The input section takes incoming signals and routes them
to the output section.
▶ The output section routes signals to broadcast, recording,
or a router.
▶ The monitor section enables signals to be heard.
▶ On-air broadcast consoles, particularly for radio, do not
have to be as elaborate as production consoles because
most of the audio they handle has been produced already.
But modern consoles for radio have sophisticated features,
such as digital signal processing (DSP), computer-assisted
operations, and routing flexibility.
▶ The features of production consoles generally include the
input/output (I/O) section consisting of an I/O channel
strip; input selector control; phantom power; microphone
preamplifier input module; microphone preamplifier; trim
or gain; pad; overload, or peak, indicator; polarity (phase)
reversal; channel assignment and routing; direct switch;
pan pot; equalizer and filter; dynamics section; channel/
monitor control; cue and effects (F/X or EFX) sends (pre- or
postfader); solo and prefader listen (PFL); mute (channel
on/off); channel and monitor faders; and meters.
▶ For acoustic sound to be processed through electrical
equipment, it must be transduced, or converted, into
electric energy. Electric energy is measured in decibels in
relation to power—dBm—and voltage—dBu or dBv, dBV,
▶ In measuring an electric circuit, a foremost concern is
impedance—that property of a circuit, or an element, that
restricts the fl ow of alternating current (AC). Impedance is
measured in ohms (Ω), a unit of resistance to current flow.
The lower the impedance in a circuit, the better.
▶ The volume-unit (VU) meter is a voltage meter that measures
the amount of electric energy flowing through the
console. The meter has two scales: percentage of modulation
and volume units. Percentage of modulation is the
percentage of an applied signal in relation to the maximum
signal a sound system can handle.
▶ Peak meters, which today are preferred over the VU meter,
track peak program levels, thereby making them a
more accurate indicator of signal levels passing through a
diodes (LEDs) or plasma displays.
▶ With the peak program meter (ppm), as signal levels increase
there is a warning of impending overload distortion.
The level indicator makes this easier to notice because its
rise time is rapid and its fallback is slow.
▶ One goal in processing audio through the signal chain is to
make sure that the levels at each stage are optimal. Given
the several stages in the sound chain, from microphone to
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console to recording to mixing to mastering, this is easier
said than done.
▶ Meters in digital audio consoles are calibrated in decibel
full-scale (dBFS), a unit of measurement for the amplitude
of digital audio signals. Zero dBFS occurs when all the
binary bits that make up the digital signal are on.
▶ The master section includes master buses, the master fader,
the master effects sends and returns, level and mute controls,
meters, and other functions.
▶ The monitor section includes recorder select, send, mix,
and speaker select switches. It may also have a pan pot,
mutes, and a phase coherence switch.
▶ Other common features of production consoles include
talkback, slate/talkback, an oscillator, and, in analog consoles,
a patch bay.
▶ A channel strip refers to one channel (usually input) of a
console. It can be ordered separately from the console and
rigged to a power supply and I/O connections for standalone
the routing of sound through pathways not provided in
the normal console design. The patch bay makes multiple
signal paths possible. Patch cords plugged into jacks connect
the routing circuits.
▶ The signal paths that are used most often are wired together
at the terminals of the patch bay. This normals these
routes and makes it unnecessary to use patch cords to connect
them. It is possible to break normal and create other
signal paths by patching.
▶ Plugs at the end of patch cords are either unbalanced,
comprising a tip and a sleeve, or balanced, comprising a
tip, ring, and sleeve.
▶ Instead of hardware-based patch panels, many modern
consoles in general and all digital consoles in particular
handle patching using computer programming.
▶ Console automation makes it possible to automate fader
functions, decoding positional information as adjustments
in level are made. The data are stored in and retrieved from
▶ There are four types of console automation systems in use:
voltage-controlled automation, moving-fader automation,
software-controlled automation, and MIDI-based
▶ Console automation systems have at least the three basic
operating modes: write, read, and update.
▶ Digital consoles use the assignable concept in three configurations:
in an analog console that is digitally controlled, in
an all-digital console, and in a virtual console which is not
a console per se but an integrated system that combines a
hard-disk computer and specialized software to record and
process audio directly to disk.
▶ With digital consoles, instead of individual controls for
channel-to-track routing on each channel strip, these functions
have been centralized into single sets so they can be
assigned to any channel. Once assigned, the commands
are stored in the console’s computer, so different functions
can be assigned to other channels. There is no physical
connection between the controls on the console surface
and the audio circuit elements.
▶ A control surface, or work surface, provides external control
of a virtual audio environment. There are two main types
of control surfaces: general-purpose controllers that can
work with a wide range of gear and dedicated controllers