Audio

Dolby Atmos

Object-based surround sound

Atmos is not a bitstream of its own, it travels inside one. That single fact decides which Diva output can carry it, and what your sources have to be told before they will send it.

Dolby Atmos is object based audio. Instead of a fixed set of channels, the mix carries a bed plus individual objects with positional metadata, and the decoder in your AVR or soundbar renders those objects onto whatever speaker layout it actually has, height channels included. It reached cinemas in 2012 and home equipment in 2014.

It is always carried inside another format. On disc that carrier is Dolby TrueHD, which is lossless and needs high bit rate audio on the HDMI link; from the streaming apps it is Dolby Digital Plus, which is lossy and fits into far less room. The distinction decides your cabling, because S/PDIF, whether optical or coaxial, tops out at 5.1 compressed audio and cannot carry either form of Atmos. An Atmos chain is an HDMI chain.

Carrying Dolby Atmos through the HDfury Diva

The Diva performs no audio format manipulation: what comes in goes out untouched. It neither builds nor strips an Atmos stream, it decides which output the stream reaches. The dedicated HDMI audio output is the one to use, a self generated 720p or 1080p video stream carrying full audio and made to feed any AVR input. Its audio can come from a source at the Diva inputs, or from ARC and eARC on TX0.

Pulling Atmos back out of a television depends on which return channel that set has. With an eARC capable input connected at TX0, the Diva extracts up to Dolby Atmos HBR over TrueHD and forwards it to the HDMI audio output on its own, with no CEC option to select. With ARC only, the ceiling is Atmos over DD+ bitstream, CEC has to be enabled, the CEC device type has to be Audio Processor, and Enable DD+/ATMOS ARC has to be ticked, which over IP is set archbr on.

Telling your sources Atmos is welcome

A source sends only what the EDID it reads allows, so an Atmos capable player handed a stereo EDID sends stereo and nothing downstream will recover it. In AUTOMIX, tick the 7.1 Full flag, or the AUDIO OUT flag so the mixed EDID reports the capabilities of the sink on the dedicated audio output rather than those of your television; the IP command is set edid audio full. In CUSTOM mode, pick one of the tables whose name ends in All Sound, such as bank 11 or bank 17. FIXED EDID presents a 2-channel table, so Atmos will never arrive while that mode is selected.

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