![Matrix mixer in rack](https://upload.wikimedia.org/wikipedia/commons/6/62/Matrix_mixer_in_rack.jpg)
A matrix mixer is an
audio electronics
Audio most commonly refers to sound, as it is transmitted in signal form. It may also refer to:
Sound
*Audio signal, an electrical representation of sound
*Audio frequency, a frequency in the audio spectrum
*Digital audio, representation of sound ...
device that routes multiple input
audio signals to multiple outputs. It usually employs level controls such as
potentiometer
A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat.
The measuring instrum ...
s to determine how much of each input is going to each output, and it can incorporate simple on/off assignment buttons. The number of individual controls is at least the number of inputs multiplied by the number of outputs.
Matrix mixers may be incorporated into larger devices such as
mixing console
A mixing console or mixing desk is an electronic device for Audio mixing (recorded music), mixing audio signals, used in sound recording and reproduction and sound reinforcement systems. Inputs to the console include microphones, signals fro ...
s or they may be a standalone product. They always have routing and level controls and may also include other features. Matrix mixers are often used in a complex listening space to send audio signals to different
loudspeaker
A loudspeaker (commonly referred to as a speaker or speaker driver) is an electroacoustic transducer that converts an electrical audio signal into a corresponding sound. A ''speaker system'', also often simply referred to as a "speaker" or ...
zones. They may be used to provide the producer or director different blends of a mixing project for
television, film or
recording studio.
Basics
In
professional audio
Professional audio, abbreviated as pro audio, refers to both an activity and a category of high quality, studio-grade audio equipment. Typically it encompasses sound recording, sound reinforcement system setup and audio mixing, and studio mu ...
, a matrix mixer is used to route
audio signals from multiple sources to different destinations.
It may be a standalone device or embedded within another, larger product such as a
mixing console
A mixing console or mixing desk is an electronic device for Audio mixing (recorded music), mixing audio signals, used in sound recording and reproduction and sound reinforcement systems. Inputs to the console include microphones, signals fro ...
,
digital audio workstation
A digital audio workstation (DAW) is an electronic device or application software used for recording, editing and producing audio files. DAWs come in a wide variety of configurations from a single software program on a laptop, to an integrat ...
or
digital signal processor.
An
analog
Analog or analogue may refer to:
Computing and electronics
* Analog signal, in which information is encoded in a continuous variable
** Analog device, an apparatus that operates on analog signals
*** Analog electronics, circuits which use analog ...
matrix mixer contains a number of simple
electronic mixer
An electronic mixer is a device that combines two or more electrical or electronic signals into one or two composite output signals. There are two basic circuits that both use the term ''mixer'', but they are very different types of circuits: ...
circuits, the quantity being the number of inputs multiplied by the number of outputs. Each electronic mixer controls the level (
gain) of one input going to one output. The level control is usually a rotating
potentiometer
A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat.
The measuring instrum ...
(called a "pot"). Each row of electronic mixer circuits, one from each input, feeds a
summing amplifier or combining amp at the output. A
fader (a linear potentiometer) may be used to control the level of each output signal. Other controls may include a mute button for each input/output intersection, a mute button for each input, a mute button for each output, and buttons that invert the input signal
polarity. The output signals of the matrix mixer may be digital, or they may be
balanced
In telecommunications and professional audio, a balanced line or balanced signal pair is a circuit consisting of two conductors of the same type, both of which have equal impedances along their lengths and equal impedances to ground and to other ci ...
or unbalanced analog. It is possible in a matrix mixer to combine an all-analog signal path with digital control of level.
Any audio console that lacks a matrix section may be connected to an external matrix mixer. Many audio manufacturers have produced matrixes incorporating
digital signal processing (DSP) which offers additional tools such as
compression
Compression may refer to:
Physical science
*Compression (physics), size reduction due to forces
*Compression member, a structural element such as a column
*Compressibility, susceptibility to compression
* Gas compression
*Compression ratio, of a ...
, equalization,
ducking
In audio engineering, ducking is an audio effect commonly used in radio and pop music, especially dance music. In ducking, the level of one audio signal is reduced by the presence of another signal. In radio this can typically be achieved by low ...
,
gating, and loudspeaker system management.
Live sound
In
live sound mixing
Live sound mixing is the blending of multiple sound sources by an audio engineer using a mixing console or software. Sounds that are mixed include those from instruments and voices which are picked up by microphones (for drum kit, lead vocals an ...
the
front of house mixing console often includes a matrix mixer section for optimizing the blend of sound going to various locations in the performance space. Subgroups, auxiliary mixes, submixes or even the main outputs are routed through the matrix mixer to different loudspeaker zones, making the matrix essentially a "mix of mixes".
A front-of-house matrix may be used at a concert to switch between the
headliner's and the
opening act's mixing consoles. A matrix mixer feature may be included on analog or digital consoles. For instance, the
Midas Consoles XL4 concert mixing console has a built-in 8×8 matrix summing 8 subgroups into 8 matrix outputs; the same basic module is available separately as the Midas XL88 (see photograph). The digital
Yamaha M7CL mixing console is another such product; it has a 19×8 matrix section summing 16 mixes as well as the main left/right/mono outputs (see screenshot). In the classic analog
monitor mixer
Monitor or monitor may refer to:
Places
* Monitor, Alberta
* Monitor, Indiana, town in the United States
* Monitor, Kentucky
* Monitor, Oregon, unincorporated community in the United States
* Monitor, Washington
* Monitor, Logan County, West V ...
without faders, the console is set up as a large matrix mixer with the addition of
equalization filters and other controls for each input.
[
]
The matrix mixer is useful for performance spaces with multiple loudspeaker zones such as main left and right loudspeaker arrays, a center loudspeaker cluster or array, under-balcony speakers for the rear seating area, stage-lip loudspeakers for the front seats, overflow rooms, green room
In show business, the green room is the space in a theatre or similar venue that functions as a waiting room and lounge for performers before, during, and after a performance or show when they are not engaged on stage. Green rooms typically have ...
s, the foyer, and broadcast or live streaming to distant audiences.[ If there is no separate monitor mixer with its own operator, the matrix mixer could be used to send a different blend to stage monitors or sidefill loudspeakers. However, such a use of the matrix is limited by the likelihood that the musicians on stage would be disturbed by any changes made to the channel levels by the front of house operator. It is usually better to supply stage monitors with signal obtained from pre-fader auxiliary sends. Listeners outside of the main performance space will not hear amplified instruments such as electric guitar as well as those inside, so the matrix output going to their location would typically contain more of the amplified instruments. Also, the matrix may be used to send a different blend to any recording devices, especially a blend that is optimized for stereo playback whereas the live sound for the performance space may be presented in mono.][ The matrix mixer may be used to combine the main mix with audience ambiance microphones to obtain a more "live" blend for the recording mix.
]
Recorded sound
In the process of mixing for film or television, a matrix mixer may be used to give the film director, television director or producer a working mix of the project while the mix engineer puts it together. In the recording studio, the same method may be used to give the record producer a different blend during the mixing process. The matrix mixer may have also been used to route various audio input channels to specific recording channels.
See also
*Matrix decoder
Matrix decoding is an audio technology where a small number of discrete audio channels (e.g., 2) are decoded into a larger number of channels on play back (e.g., 5). The channels are generally, but not always, arranged for transmission or recordin ...
, for expanding playback channels to a larger number of loudspeaker channels
*Microphone practice
There are a number of well-developed microphone techniques used for recording musical, film, or voice sources or picking up sounds as part of sound reinforcement systems. The choice of technique depends on a number of factors, including:
* The w ...
, in which matrixing may be used to produce a mono-compatible stereo image
* Merged stereo, stereo sound channels in a single signal path
References
{{reflist, colwidth=30em
External links
"Mixer Inside The Mixer: Applications Of Console Matrix Sections"
Craig Leerman, ''ProSoundWeb''.
Neumann 24x4 48 GROUP MATRIX Summing Mixer
Ben Taylor,
VintageMakerDocumentation
'
Audio mixing
Sound production technology