Venue Proofing Your Film — Audio

The Dolby 7 Standard

Cinema audio processors have a master fader setting. The correct operating level — matching the level used during professional film mixing — is Dolby 7. At this setting, a reference signal measures 85 decibels per channel, with a further 20dB of headroom for peaks. Your dubbing mixer works at Dolby 7. The cinema is supposed to play at Dolby 7. When both are correct, what the mixer hears in the dubbing suite is what the audience hears in the cinema.

Why Cinemas Turn Their Amps Down

Multiplexes are buildings where ten or more films play simultaneously in adjacent screens. The walls between screens are not always well soundproofed. A loud action film at full Dolby 7 bleeds audibly into the quiet drama next door. The easiest solution many cinemas have adopted is to turn the amplifier fader down and leave it there. Fader levels of 6.5, 6.0 and 5.5 are common. Some cinemas run as low as 4.7. We visit a lot of cinemas and check amp levels — this is not an occasional variation, it is routine.

What This Means for Your Film

A film mixed at Dolby 7 standard playing at Dolby 5.5 sounds quieter and less dynamic than its mixer intended. Quiet scenes become harder to follow. The contrast between soft and loud — the dynamic range that makes a great mix feel alive — is compressed. A film mixed for broadcast or online delivery will likely already be too loud for cinema standard; bringing it down to comply reduces the peaks your sound designer worked to achieve.

Check at Dolby 5.5

Before signing off any mix intended for cinema, ask your dubbing mixer to play you a pass at Dolby 5.5. This is not the standard — 7 is the standard — but 5.5 is the worst case you are realistically likely to encounter. Listen specifically to your quietest dialogue scenes. If they become difficult to follow at 5.5, that is worth addressing in the mix room while you still can, not after the DCP is locked.