Synchronized audio for theater playback — distinct from stereo music mixing. Larger spaces, specialized acoustics, DCP-formats with surround requirements and theatrical loudness standards.
In the cinema, sound works differently than at home—you realize this at the latest during your first mastering session. The room is larger, the speakers are professionally calibrated, and your mix has to work on systems you've never seen yourself. Cinema sound isn't just a loud stereo mix; it's a format ecosystem with its own rules: Dolby Digital, Dolby Atmos, DTS—each system has different frequency ranges, different dynamic windows, different limiting behaviors.
This starts with the mixing itself. Your 5.1 surround master must be mixed to the correct calibration level (usually 85 dB SPL in a cinema). This isn't arbitrary—it corresponds to the standard listening experience in a movie theater. If you only mix in the studio on nearfield monitors, you completely lose the spatial information. That's why sound engineers go for actual cinema tests or at least use surround systems with correct levels. Bass management is critical: the .1 channel (subwoofer) must be driven correctly, otherwise all the dialogue will sound through the subwoofer instead of the center.
Practically, this means you need a reference cinema mix that differs from a streaming mix. Streaming is compressed, often with normalization according to LUFS standards; cinema works with headroom and transient details. A gunshot in a cinema film has an energy and clarity that doesn't exist in the Netflix version—not because the cinematographer was different, but because the sound space can handle it. You mix more aggressively, allow peaks, and trust the DCP encoder's limiting technology.
Dialogue intelligibility is also weighted differently. In a 300-seat auditorium with professional acoustics, you can work more subtly than with TV standards. But to do so, you need to know how your cinema sounds. Some venues are muffled (old cinemas with poor acoustics), others are dry and precise. A good cinema sound mix should work universally—that's why standardization exists and why you should listen in at least two different cinemas, if possible.
File preparation also differs: DCP (Digital Cinema Package) preparation is not the same as MP4 export. Bit depth, sample rate, metadata—everything has consequences. And if your film is going into Atmos, another spatial dimension is added, requiring even more planning. Cinema sound is craftsmanship with high technical demands.