System Design, Installation, and Commissioning
What this domain tests
This domain tests the path from requirements to a working system: viewing and listening geometry, loudspeaker coverage, cable pathways, equipment placement, and commissioning documentation. Items often ask you to calculate spacing, identify a code issue, or verify that a design meets the client's use case.
Core rules
- Display size is driven by farthest viewer distance and content type; detailed text needs a larger image height than entertainment video. Use image height, not diagonal, in viewing-angle rules.
- Loudspeaker coverage depends on ceiling height above ear height and coverage angle. For a 90° coverage pattern, the coverage radius at the listener plane is h × tan(45°), where h is height above ears.
- Cable pathways must respect bend radius, fill, separation from power, and fire-rated penetration requirements.
- Commissioning includes as-built drawings, cable schedules, device addresses, gain and delay settings, and client training.
- Installation must follow manufacturer torque, mounting, and clearance requirements, not improvisation.
Worked example
A ceiling is 3.0 m high, listener ear height is 1.2 m, and the loudspeaker has a 90° coverage angle. Estimate the coverage radius at ear height and a simple square-grid spacing.
- Height above ears = 3.0 − 1.2 = 1.8 m.
- Half-angle = 45°, so radius = 1.8 × tan(45°) = 1.8 m.
- For a simple square grid with circles touching, spacing = 2 × radius = 3.6 m. Reasoning: use height above the listener plane, not ceiling height alone. A denser grid may be needed for even coverage and intelligibility.
Traps
- Using ceiling height instead of height above ear height.
- Sizing a display by diagonal when the viewing rule uses image height.
- Ignoring firestopping and cable separation from power.
- Commissioning without recording final DSP, network, and control settings.
- Treating as-built documentation as optional.