Channel-based audio is the traditional model in which each track is permanently tied to a specific speaker position — left, right, centre, surrounds — and the mix is created for one fixed layout like stereo or 5.1. It is simple, universal, and exactly what every legacy device understands, which is why it has carried film and music for decades. Its limitation is rigidity: a 5.1 mix assumes 5.1 speakers, so playback on a different configuration requires downmixing or upmixing that can never perfectly recover the artist's intent, and adding height or personalization means a whole new mix. Object-based and scene-based audio emerged to escape that rigidity, but channel-based remains the backbone of most delivery.
