AV Site Surveys Flashcards

During an AV site survey, what is the primary purpose of measuring the room's ambient noise level?

Answer: To establish the required signal-to-noise ratio for the audio system

Measuring ambient noise (NC/RC rating) is critical for determining how much signal headroom the audio system needs. The speech intelligibility target depends on having adequate signal above background noise.

A site survey reveals that a conference room has an aspect ratio of 2:1 (length to width). According to AVIXA standards, what potential AV design challenge does this present?

Answer: Long rooms require distributed audio to maintain even coverage

Long, narrow rooms (high length-to-width ratio) create uneven sound coverage from a single front loudspeaker cluster, requiring a distributed or delay speaker system to maintain adequate SPL at the far end.

When conducting a site survey, you discover existing conduit runs from the equipment rack to the display location. What is the MOST important measurement to record?

Answer: The conduit inner diameter and total run length

Inner diameter and run length determine whether the conduit can accommodate required cable bundles and whether pull tension will be within allowable limits. Number of bends also affects pull difficulty but the ID and length are the primary capacity factors.

During a site survey for a new display installation, you measure 850 lux of ambient light falling on the screen surface. According to AVIXA standards, what minimum projector output (ANSI lumens) should be specified for a 100-inch diagonal 16:9 screen?

Answer: Approximately 3,500 lumens

AVIXA's DISCAS standard recommends a contrast ratio of at least 15:1 on the screen. With 850 lux ambient, you need substantial projector output. A 100-inch 16:9 screen has roughly 1.17 m² of area; multiplying by the required screen luminance gives approximately 3,500 lumens as a practical minimum.

When documenting power availability during a site survey, which value is MOST critical for AV rack design?

Answer: The available amperage on dedicated circuits at the rack location

AV racks must not exceed the amperage of their dedicated circuits. Knowing available amperage at the rack location allows the designer to calculate total load, apply the 80% NEC continuous load rule, and specify appropriate PDUs and circuit breakers.

A site survey for a boardroom shows ceiling height of 3.2 m (approx. 10.5 ft). What AVIXA-recommended maximum mounting height should guide ceiling microphone placement?

Answer: 3.0 m (approx. 9.8 ft) maximum

AVIXA's Audiovisual Systems Performance Verification standard and general best practices recommend ceiling microphone mounting heights not exceed approximately 3 m (9.8 ft) to maintain adequate pickup sensitivity and avoid excessive room noise pickup.