Thread: Dolby Digital Plus

What is new in Dolby Digital Plus?

Dolby Digital Plus is a digital audio compression standard developed by the Dolby Labs to be used with both HD DVD and Blu-ray discs. It is often referred to as DD+ or E-AC-3. It has a number of improvements over the previously used legacy Dl?,lby Digital or AC-3.

While the AC-3 standard supports up to 5 channels of full range audio at a bitrate of up to 0.640 Mbitg/sec, E-AC-3 can support up to 13 channels of full range audio at a peak bitrate of 6.144Mbits/sec. However the current standards of HD DVD and Blu-ray supports only up to 7 full range audio channels.

With Dolby Digital Plus, there is no latency or loss of quality during the conversion process, hence reproducing exactly what the directors and producers intend you to hear. Furthermore, Dolby Digital Plus is also compatible with systems equipped with Dolby Digital. However, there is a certain amount of down mixing that takes place, during which a number of audio channels are mixed together to produce a lower number of channels that is supported by the system. For example, a 5.1 channel audio stream may be down mixed to a 2 channel stream for playback on a 2.1 audio system and so forth .