A High-Definition Multimedia Interface (HDMI®) amplifier is a device that is used to connect one or more input signals to multiple output connections, such as two or more high-definition televisions (HDTVs). HDMI® refers to the type of cable and connection used to connect electronic devices that transmit a high-definition (HD) signal. Simple connections are often made between two devices, such as a cable receiver with HD capabilities and an HDTV, through a single HDMI® cable. Use of an HDMI® amplifier, however, allows one signal from a cable receiver or other device to be transmitted over long distances and to multiple display devices.
Also called an HDMI® splitter, one basic purpose of an HDMI® amplifier or amp is to allow one signal source, which provides the input for the amplifier, to transmit to multiple display devices, which act as outputs from the amp. HDMI® refers to not only the type of connection used for HD broadcasting signals, but also the type of cable used to connect devices and transmit this signal. The nature of an HDMI® cable and HD signal is such that in addition to both audio and video signals, data streams with additional information can be sent through this connection. This allows HD devices to take advantage of the technological improvements that these devices have over their standard-definition (SD) counterparts.
The nature of an HD signal, and the HDMI® cable used to transmit it, is such that it can be difficult for the signal to be sent through long cables without degradation. An HDMI® amplifier, however, can be used to boost the strength of the signal to allow it to retain quality over such distances. This means that an HDMI® amplifier usually requires a dedicated power source, however, unlike some SD signal splitters or cable extenders. Digital rights management (DRM) and other types of anti-pirating software used with HD signals can also create problems for using other types of cable extenders, and so an amp is usually designed to function with such protection.
An HDMI® amplifier can also be used to allow a single signal to be sent to multiple displays at one time. If someone has a cable receiver for HD, for example, and wants video and audio from it to be sent to multiple HDTVs, then he or she is likely to need an amp. This is because an HDMI® amplifier can be designed with multiple output connections. A single input from the receiver can be connected to the amp, which then boosts the signal sufficiently for it to be sent through two or more output connections to multiple display devices.