The 2 Second Rule in Acoustics

Poor room acoustics is caused by extended sound wave reflections that produce background noise.   When the background noise raises to levels that blur original sound, communication within the room becomes strained, as crowd noise elevates.    Human ear is built to distinguish between original sound and reflected sound waves so long as the reflections (or echoes) collapse within 2 seconds inside the room.   If the echoes carry for longer than 2 seconds, the blurred sound signals begin to take hold and disguise the clarity to original sound.

A loud restaurant is the perfect example.   When the crowds gather for happy hour, the echoes take the space over due to all the hard reflective surfaces in a restaurant.   The echoes carry for up to 10 seconds, pushing well past the 2 second threshold.   To better control the noise levels in the space, sound panels are wall or ceiling mounted around the room’s perimeter, to capture and convert the echoes out of the space.   By placing the right amount of sound panels into the space, the echoes can be forced to collapse within 2 seconds, thus restoring the room to premium quality sound.   The customers no longer are forced to shout over the excessive background noise, and can converse in normal conversational tones.

The key to any sound absorbing project is to ensure that the room receives the right amount of sound panels.  That calculation can easily be derived based on the rooms size, shape and surface textures.  NetWell Noise Control runs a free Room Analysis for their clients to properly calculate that amount.   For more information on the 2 second rule and how you can control the acoustics within your space, call NetWell’s help desk at 1-800-638-9355 or visit them online at

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