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What is HDMI eARC? eARC vs ARC Tech Fully Explained Guide

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What is HDMI eARC? eARC vs ARC Tech Fully Explained Guide

HDMI Audio Extractor General Instructions and Its applications

What is HDMI eARC? What are the benefits?

Enhanced Audio Return Channel (also known as eARC) is the next generation of ARC. It’s a feature implemented in the most recent HDMI 2.1 specification. The main benefit of eARC is a big boost in bandwidth and speed. This allows you to send higher-quality audio from your TV to a soundbar or AV receiver.  So, what is HDMI eARC vs ARC? eARC is an enhanced version of ARC that provides better audio quality and greater bandwidth, allowing for up to 32 channels of audio, including eight-channel, 24bit/192kHz uncompressed data streams at speeds of up to 37Mbps.

See the comparison from: HDMI.org

Why is ARC (eARC) needed?

After learning about what is HDMI eARC, next, we want to talk about why is ARC (eARC) needed. eARC vs. ARC: What we can discover from their benefits and why you may need an HDMI audio extractor for optimal audio quality. This needs to start from the transition of analog to digital of AV signal. The traditional use of analog audio and video signals, audio (A) and video (V) signals are transmitted independently, but today’s HDMI digital AV signals, A and V signal is fed by the same signal cable. The traditional AV wiring logic is to connect A (Audio) of the signal source to the audio device, and V to the video display device. Today’s digital HDMI AV signal, not only the AV signal is bonded and fed by the same signal cable, but also after the connection between the display device (Sink) and the signal source (Source), they are also doing communication with each other. Using simple logic algorithms, the display device can present the best video resolution and sound quality. But here comes the problem. HDMI not only binds AV together, but also has its uniqueness (because of the definition of image resolution and sound format), so if an HDMI signal source needs to be connected to independent video display and audio output device, there will be wiring problems. For this reason, ARC came into being. For example, if the signal source of the Set-Top-Box is connected to the TV via HDMI, and you are not satisfied with the sound output of the TV (usually, it is not easy to output satisfactory sound effects due to the structure and size of the TV), you can just find the headphone output of the TV to connect to a stereo system with acceptable sound quality. But today’s home audio also has an HDMI interface. At this time, a TV with ARC (eARC) port can be connected to the HDMI interface of a home audio. This will be a perfect system, for example, if your audio system has 5.1 audio processing capability, through the ARC (eARC) pipeline, the signal source of the video box can output 5.1 sound data to your home audio.

Why do you need a HDMI audio extractor to get audio sources?

With their ultra-slim profiles, today’s flat screens simply don’t have the enclosure space necessary to allow drivers to give you big, punchy sound for the detail needed for dialogue-heavy scenes or big action movies. Most users place their speakers at the bottom side of the flat-screen TVs, firing out sound from loudspeaker with small box and small size speaker, and some are placed in the center on the rear of the flat-screen in an attempt to help spread the sound. Either way, they are hardly the best ways to achieve a really immersive audio. So a large number of TVs still emit a tinny, wispy sound that doesn’t do justice to the gorgeous 4K, or even 8K, picture you’re seeing. So what are the best ways to improve your television’s sound? There are some different options*2 that will instantly enhance your TV viewing experience. But it might need an independent audio source to supplement some of those options to work. Therefore, an HDMI audio extractor such as HA2-120e/ HA2-130eS/ HA2-320eS is needed for HDMI signal sources since the AV signal is bounded in a single cable physically and electronically.

*2: Options including: Desktop speakers、Use your existing hi-fi stereo system、Add a sound-bar or sound-base、5.1 home cinema surround sound (or more)、A good pair of headphones etc.

What is HDMI and HDMI ARC?

HDMI launched way back in 2002, and the first consumer kit to feature this high-tech connector hit the shops in 2004. It was billed as a convenient way to send high-quality digital picture and sound data ‘upstream’ from a source to a TV, amplifier or soundbar. As HDMI has become the popular AV connection, traditional analogue sockets such as SCART and component video have found themselves consigned to the spare parts bin. The HDMI interface has evolved over the years, with new versions (HDMI 2.1 is the latest) bringing support for new audio and video technologies such as 3D, 4K, 8K, HDR and high frame rates, to name but a few. It wasn’t until 2009 that the HDMI ARC protocol was added to the spec-sheet. It was introduced as part of HDMI version 1.4 and has been part of the specification ever since.

When would you use HDMI ARC?

Picture the scenario as followed: You have a set-top box, game console and Blu-ray player all plugged into your TV via HDMI. Or perhaps your smart TV is using a built-in video app such as Netflix or Amazon Prime Video. Either way, you don’t want to use your TV’s speakers for audio – you’d rather hear everything played through a soundbar or home cinema amplifier instead. Traditionally, you would have to connect an optical cable from the back of your TV to an optical input on your audio device. But that’s a messy solution. Theoretically, HDMI ARC solves this problem. HDMI ARC removes the need for an optical cable and allows you to send audio ‘downstream’ from a compatible HDMI socket on your TV to a compatible HDMI ARC socket on a soundbar or AV receiver.

What equipment do you need to use HDMI ARC?

To take advantage of HDMI ARC, you’ll need a television and audio processor (AV receiver or soundbar) with matching ARC-enabled HDMI sockets. Peer around the back of your TV – if it’s packing a few HDMI sockets, you need to find the one that’s labeled “(ARC)”. Labeling isn’t compulsory, but as long as your TV is a late-2009 model or newer, there should be one at your disposal. Consult the TV’s user manual if you’re unsure. With some TVs, HDMI ARC might work automatically. If it doesn’t, you’ll need to grab a remote and tweak a few of your TV settings, including turning off your TV’s built-in speakers and enabling your TV to send audio out to an external speaker or amplifier. Using HDMI ARC does not require a new HDMI cable. Any HDMI cable should be able to cope with the requirements – it’s only when we move on to eARC that this could (potentially) become an issue. But more on that later.

Are there any issues with HDMI ARC? 

Are you worried about potential lip-sync problems? HDMI v1.3, launched in 2006, added automatic audio syncing, although it was only optional. This means some ARC-enabled products will play together nicely, others might not. The biggest problem for ARC in its current guise is manufacturers have been left to pick and choose which elements of the protocol they want to include. Support for all relevant audio codecs isn’t compulsory, so you can’t simply assume that a TV will be able to send a 5.1 Dolby Digital or DTS soundtrack from a movie over ARC. Some TV manufacturers only support Dolby Digital, while others only support two-channel stereo, defeating the point. It’s worth noting that ARC doesn’t allow you to bitstream the full-fat high-quality codecs such as Dolby TrueHD, Dolby Atmos, DTS-HD Master Audio or DTS:X soundtracks that you find on Blu-rays and 4K Blu-rays. It simply strips out the core 5.1 data stream. If you want this level of functionality, you’ll need HDMI eARC. ARC can, however, allow you to receive Dolby Atmos audio from streaming services that use the format, including Netflix and Amazon Prime Video. These services embed Dolby Atmos in a Dolby Digital Plus stream, which ARC can handle.

Do I need new HDMI cables to use eARC?

According to HDMI.org, if you currently use a standard HDMI cable with Ethernet, or a High-Speed HDMI cable with Ethernet, you should be fine. Ultra High-Speed HDMI cables with Ethernet will definitely work. Because of the extra bandwidth needed for some audio formats over eARC, it’s possible that very old cables could struggle. In January 2020, HDMI.org announced a mandatory certification programme that will ensure any cable labeled Ultra High Speed supports all HDMI 2.1 features including eARC.

eARC vs ARC: Is eARC backwards compatible with ARC?

If your TV is HDMI eARC enabled, but your AV amp or soundbar is only compatible with HDMI ARC, you’ll likely get a sound – but the bandwidth restrictions of ARC means that you won’t be able to experience the high bitrate audio that eARC can provide. So no, it is not completely backwards-compatible. Some AV receivers and soundbars that don’t have HDMI 2.1 chipsets can be upgraded to support eARC, but it varies between manufacturers and products. It depends if they are using compatible hardware that can accept the necessary firmware update. Time will tell how well-integrated eARC will be, but we are hoping adoption becomes as ubiquitous as HDMI ARC seems to be now.

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