Dolby Digital

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What Does Dolby Digital Mean?

Dolby Digital is a digital audio technology developed by Dolby Laboratories that helps reduce the data required for producing high-quality audio. Dolby Digital is considered as the industry standard for surround audio and has compatible application systems worldwide. Using advanced encoding and decoding technology, Dolby Digital is capable of reproducing multi-channel audio, which helps in delivering a cinematic audio experience to the users.


Dolby Digital was formerly known as AC-3.

Techopedia Explains Dolby Digital

Like the DTS technology, Dolby Digital also makes use of six channels:

  • Center
  • Left
  • Right
  • Left surround
  • Right surround
  • Low-frequency effects

Dolby Digital technology is based on the principle of how the human ear processes audio. By focusing on masking, eliminating and reducing the noise, Dolby Digital reduces the data required to produce high-quality audio, but maintains the essential amount of data to ensure good fidelity. It has also introduced surround formats such as Dolby Digital Plus, Dolby Digital EX, Dolby Digital Surround and others.

The benefits of Dolby Digital include easy access to software, comparatively larger software options, accurate transfer to disc from channel levels and great audio for music and movies. The code used in Dolby Digital is considered to be quite efficient and is thus capable of running at a lower bit rate.

One disadvantage of Dolby Digital is the degradation in the quality of the audio and video due to its higher compression level.

Dolby Digital is widely used in applications such as HDTV broadcast, digital cable, digital versatile discs, satellite transmission and game consoles. Discs supporting the Dolby Digital technology are usually marked with the Dolby logo.


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Margaret Rouse
Senior Editor
Margaret Rouse
Senior Editor

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.