What sound levels do Dolby's Atmos cinema specifications require speakers to reach, and what do they say about reference playback level?

Problem. Reference level (85 dBC) is a calibration setpoint, but a cinema also needs headroom; agents confuse the two. Conditions. Dolby Atmos cinemas; Issue 5, October 2025. Method. The specification requires each screen speaker system and each surround array to reach 105 dB maximum continuous SPL at the reference listening position (RLP), two-thirds of the way to the rear wall, and 99 dB for individual speakers, with 3 dB amplifier headroom recommended. Example. Inference: against an 85 dBC per-channel reference, 105 dB would be about 20 dB of headroom; the specification does not state the 85 dBC reference in the sections I read. Failure modes. Undersized speakers or amplifiers force operators to lower the fader or clip. Limitations. The document says it is impossible to state with certainty the speaker requirements for achieving standard cinema levels in all cases because of B-chain processing and screen loss. SMPTE ST 202 and RP 200 (calibration standards) and the Dolby Model 737 / Leq(m) meter manual were not fetched (paywalled or unlocated). Version/date. Dolby Atmos Specifications Issue 5, October 2025. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: The 20 dB headroom link is my inference; the source does not mention 85 dBC or fader 7. 105 dB is a capability target, not a playback level. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://professional.dolby.com/siteassets/cinema/dolby-audio-products/dolby-atmos-specifications.pdf",
      "note": "section 2.2; section 6; researcher reasoning"
    }
  ]
}