Audio Video News

If the advent of Dolby Atmos in home surround gear has pricked up your ears, you may be interested to hear that object-oriented surround will also be part of the forthcoming ATSC 3.0 broadcast TV standard. That doesn’t mean Atmos itself is hitting the airwaves. Instead, other surround encoding systems will be tested this summer from Dolby, DTS, and a consortium of other companies.

All support High-Order Ambisonics, a “scene-based” format that maps encoded objects onto whatever speakers are available, as well as speaker layouts up to 7.1.4 (an established Atmos configuration with four height channels) and 22.2 (the surround standard of Japan’s Super Hi-Vision, adding numerous height and center channels).

Dolby’s AC-4 would travel from TV to A/V receiver through the HDMI Audio Return Channel. Initially the TV would decode the AC-4 signal to a format acceptable to the receiver, presumably Dolby Atmos. In later generations, the AVR would incorporate AC-4 decoding, and the TV would pass a bitstream for decoding in the AVR. AC-4 supports 5.1 surround and stereo as well as object-oriented surround and requires only half the bandwidth of the already pretty efficient Dolby Digital Plus.

DTS:X, from Dolby’s arch-rival, can be decoded by a TV or set top box, passed via HDMI output, or transcoded to DTS 5.1 and passed via HDMI ARC or digital optical connection. DTS says objected-oriented audio can be rendered and played back on 5.1- or 2-channel systems and the signals could potentially be read by the DTS:X decoders in new upcoming AVRs. DTS also proposed its Headphone:X technology for headphone consumption of ATSC surround signals.

The third proposed standard is MPEG-H from Fraunhofer, Technicolor, and Qualcomm. It operates in either a scene-based or channel-based manner at bitrates of 96-256 kbps for “good to excellent quality” or 384 kbps for “immersive reproduction.” MPEG-H would work with loudspeakers, soundbars, tablets, or headphones.