E-AC-3 (Enhanced AC-3), branded Dolby Digital Plus, is the streaming-era successor to AC-3, used by Netflix, Disney+, Apple TV+, Amazon Prime, and ATSC 3.0. It is more bitrate-efficient, reaches higher rates, and supports more channels, so 5.1 and 7.1 stream comfortably at a fraction of AC-3's bandwidth. Its most important trick is Joint Object Coding (JOC), which layers Dolby Atmos objects on top of a 5.1 core — this is how immersive audio actually reaches most living rooms today. E-AC-3 is widely hardware-decoded across TVs, mobile, and set-top boxes, making it the practical default for premium streaming surround.
