▶ Consoles and mixers take input signals and amplify, balance

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

mixers.

▶ 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,

and dBFS.

▶ 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

console.

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

use.

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

computer memory.

▶ There are four types of console automation systems in use:

voltage-controlled automation, moving-fader automation,

software-controlled automation, and MIDI-based

automation.

▶ 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