ARC and eARC both send sound from your TV to a soundbar or receiver over one HDMI cable. The difference is how much audio fits through, and that decides whether you get lossless Dolby Atmos. Here's what each one carries, when ARC is enough, and how to set up eARC.
eARC carries lossless and uncompressed audio; ARC doesn't. eARC has about 37 times ARC's bandwidth, enough for Dolby TrueHD Atmos, DTS:X, and 7.1 PCM from Blu-ray players and game consoles.
Plain ARC is fine for streaming apps, including Dolby Atmos from Netflix and Disney+, which arrives as Dolby Digital Plus. You need eARC on both the TV and the sound system to use it.
HDMI normally carries picture and sound in one direction: from a source, like a streaming stick or game console, to your TV. ARC (Audio Return Channel) lets sound travel the other way over the same cable, from the TV back to a soundbar or AV receiver. That means the TV's built-in apps, antenna, and anything plugged into the TV can play through your sound system without a separate optical cable. ARC also lets you control the soundbar's volume with your TV remote, using HDMI-CEC.
ARC arrived with HDMI 1.4 in 2009. Its weakness is bandwidth: it has about the same capacity as an optical cable, so it can only carry compressed surround sound.
eARC (enhanced Audio Return Channel) came with HDMI 2.1. It does the same job with far more bandwidth, roughly 37 Mbps versus about 1 Mbps for ARC. That's enough for uncompressed and lossless audio: up to 7.1 channels of PCM, Dolby TrueHD, and DTS-HD Master Audio, including the lossless versions of Dolby Atmos and DTS:X found on 4K Blu-ray discs.
eARC also makes automatic lip-sync correction mandatory and handles the handshake between TV and sound system more reliably, so you're less likely to see audio drop out when switching inputs.
| ARC | eARC | |
|---|---|---|
| Introduced with | HDMI 1.4 (2009) | HDMI 2.1 (2017) |
| Bandwidth | About 1 Mbps | About 37 Mbps |
| Stereo PCM | Yes | Yes |
| 5.1 / 7.1 uncompressed PCM | No | Yes |
| Dolby Digital, DTS | Yes | Yes |
| Dolby Digital Plus (incl. streaming Atmos) | Yes, on most TVs | Yes |
| Dolby TrueHD, DTS-HD MA (lossless Atmos, DTS:X) | No | Yes |
| Automatic lip-sync correction | Optional | Required |
| Cable needed | Any High Speed HDMI | High Speed with Ethernet or Ultra High Speed |
Sometimes, and this is the most common point of confusion. Streaming services like Netflix, Disney+, and Apple TV deliver Atmos inside Dolby Digital Plus, a compressed format that fits through ARC on most modern TVs. So a soundbar connected over plain ARC can often play Atmos from the TV's own apps.
What ARC can't carry is lossless Atmos, which comes wrapped in Dolby TrueHD on 4K Blu-ray discs, or multichannel PCM, which game consoles often output. For those, you need eARC, or you need to plug the source directly into your receiver or soundbar instead of the TV.
You can live with ARC if:
You want eARC if:
Most TVs from the last few years, and every TV in our PS5 and Xbox guides, support eARC on one HDMI port. Most Atmos soundbars and current AV receivers do too.
Still getting dropouts or no sound? Our eARC troubleshooting guide walks through every fix. For a step-by-step setup with pictures of the ports, see how to connect a soundbar to a TV.
eARC is backward compatible. If your TV has eARC and your soundbar only has ARC, or the other way around, they'll connect and fall back to ARC, with ARC's format limits. You only get eARC when both ends support it.
An optical (TOSLINK) cable carries roughly the same formats as ARC, except it can't carry Dolby Digital Plus, so no streaming Atmos. ARC is the better choice because it also passes volume control and power commands between the TV and sound system. Use optical only if your TV or soundbar has no ARC port, or as a workaround when HDMI-CEC misbehaves.