As for the audio interface of projection, different types of projector interfaces have different functions.

1. AUX interface

Aux is the abbreviation of “auxiliary”.

Aux interface is the most common audio interface, which is generally divided into 2.5mm and 3.5mm specifications.

2. RCA Ports

RCA Ports is often called the Lotus ports. Using an RCA cable to transmit analog signals is the most common audio connection at present.

The full name of RCA is Radio Corporation of America, which introduces this kind of port.

Since each RCA cable is responsible for transmitting the audio signal of one channel, a pair of cables are required for a stereo signal. For a multi-channel system, the same number of cables should be equipped according to the actual number of channels. Stereo RCA Audio connectors generally mark the right channel in red and the left channel in blue or white.

3. XLR Interface

XLR Interface is also called as cannon plug or cannon connector. It gets the name because of the founder of the manufacturer Cannon Electric is Mr. Cannon.

Later, the product has been improved and added a latch. The name changed into Cannon XL. Then, the product added Rubber compound. People combined the first letter of the two words (XL and Rubber) and called it XLR Connector.

Due to the locking device, the XLR connection is quite secure. XLR connectors are also often seen on microphones, electric guitars, and other equipment.

4.  Coaxial

The standard of Coaxial is SPDIF (Sony / Philips Digital InterFace). It mainly provides the transmission of the digital audio signals. Its joints are divided into RCA and BNC.

Its high transmission bandwidth ensures the quality of audio. Although the standard connector of coaxial digital cable is a BNC connector, RCA connector is mostly used for coaxial digital wire on the market.

5. Summary

The audio interface is divided into input and output. The former uses the built-in speaker of the projector to make sound, and the latter transmits the audio information input by HDMI into the projector to the external speaker. Generally speaking, the audio interface usually adopts Lotus interface or 3.5mm interface.