Digital Video Television Sound

The standard sound format for European digital television comes in the form of MPEG-2 Stereo. This system can carry two channels of CD quality digital audio. The quality of audio this delivers is little different to that possible using the NICAM Stereo Audio system for digital stereo sound with used by terrestrial analogue television broadcasts in the UK television programmes for the last few years.

As with NICAM, the MPEG-2 Stereo sound can be encoded with the 4-channel Dolby Surround audio suitable for any home Dolby Pro-Logic decoder. Unfortunately, the technology for encoding and transmitting digital surround sound – such as Dolby Digital or even MPEG-2 Multichannel – has not been included in the first generation hardware and software, and is currently incompatible with the digital television systems in use at the turn of the millennium. The official explanation as to why Dolby Digital has been excluded is because the terms of the UK Digital TV standard prevents the use of a proprietary sound system above the MPEG-2 technology used for both picture and sound data compression.

The situation is different elsewhere around the world, however, with several countries having adopted Dolby Digital as the sound format for DTV. The FCC standard for HDTV in the USA includes Dolby AC-3 audio in the specification. This allows for surround sound made up of 5.1 channels of audio, each of which can be sent to up to five separate speakers and a subwoofer.