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Connect it all, the right way round
Tell us what you have. You get where each cable goes, what picture and sound every source then gets, and the settings that make it work.
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How the signal travels
Every source sends picture and sound down one HDMI cable. Something has to decode the sound, and something has to show the picture. With an AV receiver the usual layout is every source into the receiver, one cable from the receiver to the TV: the receiver takes the sound off and passes the picture on. The cable to the TV also brings sound back from the TV's own apps, over ARC or eARC. A soundbar without enough inputs works the other way round: sources into the TV, and the TV sends their sound back to the soundbar.
Two things break that simple picture. A receiver that cannot pass 4K at 120 Hz forces a choice for games consoles: through the receiver at 60 Hz, or straight into the TV at 120 Hz with the sound coming back over eARC. And a TV's sound return limits everything plugged into the TV.
ARC, eARC and optical: what each carries
| Link | Carries | Atmos |
|---|---|---|
| Optical (Toslink) | Stereo PCM; 5.1 Dolby Digital or DTS | No |
| HDMI ARC | Stereo PCM; 5.1 Dolby Digital, Dolby Digital Plus, DTS | Streaming Atmos (in Dolby Digital Plus) |
| HDMI eARC | Up to 8 channels of PCM; lossless Dolby TrueHD and DTS-HD Master Audio | Streaming and disc Atmos, DTS:X |
Streaming services deliver Dolby Atmos inside Dolby Digital Plus, which ARC can carry. Discs carry it in Dolby TrueHD, which needs eARC or a direct HDMI connection to the receiver. Games consoles mostly send 7.1 PCM, which also needs eARC or a direct connection; over ARC or optical they fall back to 5.1 Dolby Digital or stereo.
Which HDMI cable
- Ultra High Speed HDMI (certified for 48 Gbps): 4K at 120 Hz, VRR, and the receiver-to-TV link.
- Premium High Speed HDMI (certified for 18 Gbps): 4K at 60 Hz with HDR, enough for disc players, streaming boxes and set-top boxes.
- eARC: HDMI Licensing advises a High Speed HDMI cable with Ethernet, or Ultra High Speed.
- Long runs, as a rule of thumb past about 3 m for 4K 120 Hz or 8 m for 4K 60 Hz: an active or optical (fibre) cable. Optical HDMI cables work one way round, and not all of them carry ARC or eARC.
Questions people ask
Should a PS5 or Xbox go into the receiver or the TV?
Into the receiver if it passes 4K at 120 Hz and VRR. If not, into a 4K 120 Hz input on the TV, with the sound sent back over eARC as 7.1 PCM: nothing is lost. Over plain ARC you would get 5.1 Dolby Digital at most.
Why does my receiver show PCM?
Something upstream decoded the sound: a TV set to PCM, a player with secondary audio on, or a source set to PCM. Our guide to PCM and the no-Atmos troubleshooter go through it.
Do I need eARC for Dolby Atmos?
Not for streaming: ARC carries Atmos in Dolby Digital Plus. For discs played through the TV, yes; or connect the player to the receiver and it does not matter.
Does this tool know my model?
Not yet: you choose what your equipment can do. Every model's manual lists its HDMI inputs, which ones take 4K at 120 Hz and which one is eARC. Menu names in the settings are examples; they vary by brand.