Looking back at HDMI version 1.0, when the
HDMI CABLE connected to the theater equipment, the use of each machine needs to be individually manipulated, the whole process down, quite a hassle. So in order to simplify the control, when HDMI was upgraded to version 1.2a, a new feature was added - CEC, which requires only one person remote control, can control all the machines that support the CEC function, and no longer need to use multiple remote controls.
As a straightforward example, a CEC-enabled player, amplifier, TV, sound wall, etc. can be connected so that when the machine is turned off, all systems can be turned off by simply pressing the power button on the TV's remote control, eliminating the need to turn off the player or sound wall individually. This “convenience feature” is seldom identified separately, because devices that support HDMI ARC and HDMI eARC functions all support CEC downstream.
2 HDMI ARC - Audio Return Channel
In the traditional connection, the transmission of audio and video signals is usually like this: TV boxes, players and other output devices, connected to the amplifier via HDMI. Then the amplifier separates the video and digital audio signals, the video signal is transmitted to the TV through HDMI, the digital audio signal is decoded through the amplifier, the audio output sound.
This looks like nothing wrong, but when the TV needs to transmit sound, the trouble comes. After all, we are in the era of smart TV, TV through the network way to get the source, can be seen as playing local sources. The ordinary HDMI interface, not as a signal source to transmit signals to the outside world; if you want to connect the amplifier or audio, only through the fiber optic, coaxial interface connection. Not only is the connection cumbersome, but also can not transmit some high-specification audio tracks.
To solve this trouble, HDMI ARC was born. In support of ARC transmission of the HDMI interface, the TV can be through the HDMI cable, the audio signal back to the amplifier, stereo, do not need to additionally use optical fiber or coaxial cable connection.ARC's excellent characteristics, but also major TV, audio and video manufacturers have introduced HDMI ARC interface to the device, instead of the ordinary HDMI interface, set off a new round of changes in the audio and video industry.
3 HDMI eARC - Enhanced Audio Return Channel
When the HDMI cable evolved to version 2.1, it was already able to transmit 8K, Dynamic HDR (HDR Dynamic Data), Variable Refresh Rate (VRR) and other images. So in order to accommodate the increased video picture quality, the sound aspect had to be enhanced as well. The sound quality advanced HDMI 1.4's ARC to eARC, which is the Enhanced Audio Return Channel. How does this differ from ARC?
Overall, the functional characteristics of these two are common, and eARC can also support ARC functions. The differences brought by the technical enhancement are mainly manifested in the following: Firstly, it is the enhancement of transmission rate. the wideband of ARC is probably limited to 1-3Mbps, while eARC can reach about 37Mbps. Second, more audio formats are supported. This is also a benefit of the wideband enhancement, which allows for the transmission of next-generation lossless audio tracks, such as DTS:X and lossless Dolby TrueHD, while ARC can only transmit lossy Dolby Atmos (Atmos/DD+)
Dongguan Fenfei Electronics Co., Ltd.
