Noise Criteria

Includes Heating, Venting, and Air Conditioning (HVAC)

What Happens Here:


Issue the Noise Criteria (NC) specification with the theater’s HVAC service guidelines for the Owner’s mechanical contractor to achieve the desired ambient noise levels, the comfort temperature for film viewing, and the cooling of A/V equipment.

Insight:

Some years ago at the domed building where the Mormon Tabernacle Choir resides I witnessed a demonstration on the acoustics of the auditorium. Without the aid of a microphone and some 150 feet away from the demonstration I heard the pin drop on the floor. Amazing, and perhaps equally impressive was the length of time we held our collective breaths so as not to interfere with those sounds. Often the most dramatic moments in movies are accompanied by near-quiet sounds – insects in the dark of night, the shuffling of feet, even the shallow breathing of a nervous character, etc. – that give movies real-life believability.

These essential sounds to a movie can be missed due to the background noise in the room. If you have ever been annoyed at your local Cineplex with the chatter of the viewer next to you then you understand what background noise is. A well-designed home theater should have a background noise of (<) NC20. That’s less than “very quiet” but anything higher affects low level detail and the A/V system dynamics.

Although home settings can approach, even best the quiet of your local Cineplex, the whoosing, hissing, and rumbling of your home’s HVAC system can kick you right out of your Immersive RealismTM experience. The optimal solution is typically, but not always, to engineer a separate low-noise HVAC system for the theater.

Reference:

Not many HVAC contractors know how-to build low-noise ventilation. We provide
guidelines and, optionally, will supply engineering specs.