In electronics, a distribution amplifier, or simply distribution amp or DA, is a device that accepts a single input signal and provides this same signal to multiple
isolated outputs.
These devices allow a signal to be distributed to multiple destinations without
ground loops or signal degradation. They are used for a number of common engineering tasks, including multiple amplification,
cable television
Cable television is a system of delivering television programming to consumers via radio frequency (RF) signals transmitted through coaxial cables, or in more recent systems, light pulses through fibre-optic cables. This contrasts with broa ...
, splitting monitor and
front of house
In the performing arts, front of house (FOH) is the part of a performance venue that is open to the public. In theatres and live music venues, it consists of the auditorium and foyers, as opposed to the stage and backstage areas. In a theatre, t ...
mixes, and "tapping" a signal prior to sending it through effects units to preserve a "dry" signal for later experimentation.
Audio distribution amplifier
An Audio Distribution Amplifier also known as: a press feed; a pool feed; a media feed; press box; or an ADA, takes a single audio feed, usually a line input, but it may be a microphone input, and outputs multiple line or microphone outputs. This can be done using a passive feed, where the signal is split among the outputs, or as an active feed where the outputs are amplified. The primary use of the Audio Distribution Amplifier is to share a single audio feed with multiple members of the press pool. Thus the names press feed, pool feed and media feed.
Video distribution amplifier
A Video Distribution Amplifier (also known as a distribution amp or VDA) takes a video signal as an input, amplifies it, and outputs the amplified video signal to two or more outputs. It is primarily used to supply a single video signal to multiple pieces of video equipment. It adjusts the
amplitude
The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). The amplitude of a non-periodic signal is its magnitude compared with a reference value. There are various definitions of amplit ...
of a video signal to compensate for loss of signal in a video distribution system. Extending the distance of the video signal is the main purpose of the VDA. There are VDAs built for all video formats,
NTSC
The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...
,
ATSC
Advanced Television Systems Committee (ATSC) standards are an American set of standards for digital television transmission over terrestrial, cable and satellite networks. It is largely a replacement for the analog NTSC standard and, like that ...
, QAM16, QAM32, QAM64,
Composite Video
Composite video is an analog video signal format that carries standard-definition video (typically at 525 lines or 625 lines) as a single channel. Video information is encoded on one channel, unlike the higher-quality S-Video (two channels) a ...
and
Component Video
Component video is an analog video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video (CAV) information that is transmitted or stored as three separate signals. Compon ...
.
Their construction and capabilities can be simple; accept input signal, amplify, then output. Others can be more sophisticated that allow remote control from a control station, allow adjustment of the gain, equalization, and provide status of the input and output signals through Ethernet networks.
See also
*
Microphone splitter
References
External links
Info about some very common distribution amplifier types.Press feeds from distributor Whirlwind USA.
Consumer electronics
Film and video technology
Video hardware
Television technology
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