AC3 stands for Audio Coding 3, and is a file extension for audio files in the environment. It was created by Dolby Laboratories in 1987 for use on DVDs, Blu-ray players, HDTV programming and home entertainment systems. The AC3 format contains up to 6 discrete sound channels. The 5 most frequently used audio channels are dedicated to normal range speakers (20 to 20,000Hz) and 1 channel is for the low frequency sub buffer effect (20 to 120Hz). Specifically, they are left front, right front, center, left rear, right rear, and an ultra-low track called Channel 5.1, which is the standard background sound most used in commercial and domestic cinemas.
Category: Audio File
Popularity: Popular with domestic movie enthusiasts
Developer: Dolby Laboratories
Facts about AC3
AC3 can operate sound frequencies from 20 to 20,000Hz, which is equivalent to the human auditory frequency. This means that AC3 can produce a diverse, detailed and unique sound effect for people.
Most HDTV programming today adopts the standard AC3 format. Together with an HD television broadcast, it makes everything more realistic, especially the sound.
Previously it was not AC3 but Dolby Pro Logic 4.0 the standard format adopted by the company. Dolby Pro Logic 4.0 can be found on many VHS tapes edited in the 1980s.
The AC3 audio bitrate on DVDs is up to 640kbps and has an average rate of up to 48kHz.
Pros: AC3 is accepted as the industry standard for DVDs and DTV. Almost all the soundtracks of DVD movies have AAC format. AC3 is highly compressed in a small file, but the sound effect is faithfully preserved as the original DVD. AC3 can be converted to various types of video files such as AVI and MPEG, which can achieve the sound quality of 5.1 Dolby Digital Surround when played in media players.
Cons: AC3 is widely used on DVDs and very rarely used in other fields. Although AC3 is compatible with 7.1 channels, when it comes to audio CDs it is only compatible with a maximum of 5.1 channels and is limited to 448kbps.
AC3 VS. AAC
AAC or Advanced Audio Coding is very different from AC3. AAC is a type of digital audio format that is promoted as the successor of MP3 because it generally achieves better sound quality with the same file size. The AAC format is a more advanced format than the AC3 format. It will create better sound quality than AC3 with the same bitrate, especially at low bitrates. Below is a more in-depth comparison between AC3 and AAC.
History:
AC3 was developed by Dolby Laboratories and was originally called Dolby Stereo Digital until 1994. This format has been adopted as the international standard of Moving Picture Experts Group since 1997.
AAC was developed in cooperation with AT&T Bell Laboratories, Dolby Laboratories, Sony Cooperation, Nokia and Fraunhofer IIS. In 1997, Moving Picture Experts Group declared AAC an international standard.
Quality:
The AC3 file format is a 6-channel environment sound that provides a total bitrate of 384 kilobits per second and is compatible with frequencies up to 48 kHz. You must use a Dolby Digital compatible amplified cinema system to reproduce the full effect of an AC3 track.
AAC can store a large amount of audio information using little space. It is a more advanced audio format than AC3. Its average frequency ranges from 8 to 96 kHz, so the sound quality is better than that of AC3 when the audio file is encoded at low bitrates.
Compatibility:
AC3 is widely used as a standard soundtrack for DVDs, Blu-ray, HDTV programming and game consoles.
Apple adopted AAC as the default format for iTunes and iPod since 2003. Most devices and players are compatible with the AAC format. Many car sound systems adopt AAC.
