Acoustics before equipment
- Target speech transmission index (STI) of 0.60 or better across the seating area; 0.50 is the floor for acceptability.
- Reverberation time appropriate to use: roughly 0.6–0.9 s for speech-led halls, longer only where music performance is a stated requirement.
- Background noise from HVAC at NC 25–30 in the audience area.
- Treat rear-wall slap echo and parallel side walls before adding loudspeaker power.
- Confirm the acoustic scope has a named owner — it is the item most often deleted at value engineering.
Sightlines and display sizing
| Parameter | Benchmark | Note |
|---|---|---|
| Farthest viewer distance (detailed content) | ≤ 4× image height | Spreadsheets, CAD, dense slides |
| Farthest viewer distance (basic content) | ≤ 6–8× image height | Video, large-type presentations |
| Minimum text height | 1/200 of the farthest viewing distance | Test with real slides, not a test pattern |
| Bottom of image above floor | ≥ 1.2 m, verified against rear-row heads | The most common retrofit complaint |
| Horizontal viewing cone | Within ±45° of screen centre | Seats outside this are effectively audio-only |
| Ambient light on screen | Controlled; specify projector/LED to measured lux | Glass-walled halls need LED, not lumens |
Audio system checklist
- Even coverage: ±3 dB across the seating area, verified by measurement.
- Headroom above the design SPL so the system never runs into limiting during a live event.
- Assistive listening provision where the brief or local accessibility policy requires it.
- Microphone plan tied to the actual event formats — panel, lectern, roving, hybrid.
- Feedback stability margin tested with the real microphone positions, not on a bench.
- DSP configuration files documented and handed over.
Control, hybrid and operations
- One-touch presets for the three formats staff run weekly; everything else behind an advanced page.
- Hybrid meeting path tested with the organisation's actual conferencing platform.
- Camera framing presets tuned to the lectern and panel positions.
- Remote monitoring and asset management for multi-room estates.
- Named staff trained, with a laminated one-page operating card in the rack room.
Acceptance testing
- Measured STI and SPL coverage plots across the seating area.
- Display uniformity, contrast and text-legibility check from the last row.
- Full end-to-end rehearsal of each event format with client staff operating.
- Signed as-builts, rack elevations, cable schedules and configuration backups.
- Warranty, spares and response-time terms agreed in writing before final payment.
Frequently asked
- What speech intelligibility target should an auditorium meet?
- Design for an STI of 0.60 or better across the seating area, with 0.50 as the minimum acceptable floor. Intelligibility, not loudspeaker brand, is what audiences actually experience.
- How large should an auditorium display be?
- Size it from the farthest seat: within about 4× image height for detailed content and 6–8× for basic content, with the smallest on-screen text at least 1/200 of the farthest viewing distance.
- Projector or LED wall for a hall with daylight?
- In a glazed, daylit hall, direct-view LED is usually the correct answer. Beyond a point, adding projector lumens costs more and delivers less contrast than an LED wall sized to the room.
- What should be included in AV acceptance testing?
- Measured intelligibility and coverage plots, a legibility check from the last row, a full rehearsal of every event format with client staff at the controls, and a documentation pack including configuration backups.
Cite this reference
Arif Khan, “Auditorium & Enterprise AV Specification Checklist”, arifkhanglobal.com, 2026.
Free to quote and republish in part with a link to arifkhanglobal.com/resources/auditorium-av-specification-checklist.