Dolby Digital Logo – Dolby Digital is the name of a series of technical audio data compression lossy developed by Dolby. The standard AC3 is a method for compressing digital sound which was formalized in 1992. It allows up to 6 independent channels of sound with a sampling rate of 32, 44.1 or 48 kHz and with a transfer rate of 32 to 640 kbit / s. The Dolby Digital uses this coding principle, which is why it’s often called by that name.
The Dolby Digital 5.1 has 6 channels with 5 (front left, center, front right, rear left and rear right) use the full bandwidth (20 Hz to 20 kHz) and the last channel uses only the optional subwoofer (below 120 Hz) to power a subwoofer commonly called subwoofer. Batman Returns was the first film that used the Dolby Digital during the summer of 1992 in cinemas. The first film Home theater compatible with Dolby Digital was Danger format laserdisc in 1995.
Dolby Digital includes several technologies that include Dolby Digital, Dolby Digital EX, Dolby Digital Live, Dolby Digital Surround EX, Dolby Digital Plus and Dolby TrueHD.