When a movie studio put that text on a VHS or DVD release, they were telling the home viewer: You are about to see a movie that was designed for the best sound in the world, even if you are hearing it through your TV’s single speaker.
Dolby Digital’s genius was its subtlety. It etched the digital data between the sprocket holes of the film print—a tiny, high-density checkerboard pattern. This allowed the same print to carry both the legacy analog Dolby Stereo track and the new 5.1-channel digital track. If the digital data was unreadable (due to dirt or a splice), the projector would seamlessly fall back to the analog track. It was a safe, backwards-compatible Trojan horse. dolby digital in selected theatres
For much of the 20th century, the cinema industry relied on analog optical soundtracks. While effective for their time, these tracks suffered from limitations in dynamic range, frequency response, and susceptibility to wear and tear. As the film industry moved into the blockbuster era of the 1970s and 1980s, the demand for higher fidelity sound grew. Dolby Laboratories, having already revolutionized audio noise reduction with Dolby A and Dolby SR (Spectral Recording), sought to bridge the gap between the studio master and the theatrical experience. When a movie studio put that text on
By the late 2000s, the industry began transitioning away from 35mm film entirely toward Digital Cinema Packages (DCP). In this era, the phrase "In Selected Theatres" began to fade, replaced by distinctions like "RealD 3D" or "IMAX." This allowed the same print to carry both