HDMI 2.1 promises features such as 8K/10K video output, dynamic HDR, or enhanced audio return channel (eARC), but so far I had not seen any hardware boasting support for the new specifications. It’s not really surprising, as the HDMI Compliance Test Specifications (CTS) for HDMI 2.1 is expected to be released in stages starting in Q2 2018.
While I have yet to see any HDMI 2.1 capable TV, Yamaha is already showing off a 5.1 A/V receiver allegedly HDMI 2.1 via their upcoming RX-V385 model that will be sold for $299.95 in the US.
- 5.1-Channel powerful surround sound
- Bluetooth for wireless connectivity
- HDMI 2.1 with HDCP 2.2 (4 in/1 out)
- 4K Ultra HD support, HDR10, Dolby Vision, Hybrid Log-Gamma and BT.2020
- YPAO auto-calibration technology for ideal sound
That looks good, and if we look into the details specifications we can see HDMI eARC (part of HDMI 2.1) will be supported via a firmware upgrade, however video pass-through appears to be limited to 4K 60p, 4:4:4, so that should mean the first “HDMI 2.1” A/V receivers may only support a subset of HDMI 2.1 specifications, not be future-proof with 8K pass-through, and possibly lacking support for other HDMI 2.1 features.
As a reminder, eARC supports up to 37 Mbps bandwidth enabling high-bitrate home theater audio formats, object-based audio, uncompressed 5.1 and 7.1, and 32-channel uncompressed audio.
HD Guru also reports that beside the mode Yamaha model, Denon plans to add eARC capabilities to its current AVR-X6400H and new AVR-X8500H audio video receivers through a firmware update scheduled for mid-July. The company did not mention HDMI 2.1 by name however, which may be more accurate/honest since 8K is not supported either on those higher-end models.