XLR JACK
The XLR connector is a type of electrical connector primarily used in professional audio, video, and stage lighting equipment. XLR connectors are cylindrical in design, with three to seven connector pins, and are often employed for analog balanced audio interconnections, AES3 digital audio, portable intercom, DMX512 lighting control, and for low-voltage power supply. XLR connectors are included to the international standard for dimensions, IEC 61076-2-103.[1] The XLR connector is superficially similar to the smaller DIN connector, with which it is physically incompatible.
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