Interrupted Noise; Impulse Noise; Interrupted Noise Example - 3M SP-SE-2-1/1 User Manual

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Reverberation (RT60) methods

Interrupted noise

The Interrupted noise method, applied with pink noise, is used with a portable
sound system, such as a dodecahedral speaker, or with an existing sound system
(only recommended if the sound system has a quality, omni-directional, sound
system.) With the interrupted noise method, the sound source emits a high-level
source and falls-off, returning to its original ambient background level. The Reverb
Time is measured between T
 NOTE: T
ensure an accurate sound level capture

Impulse noise

The Impulse noise method requires a broad-spectrum impulsive noise source, such
as a starter pistol, in a room to be tested. Typically, the RT60 decay start will begin
at a high-level source and decays, reporting a Reverberberation Time.
and T
1
is calculated from two reference points on the regression line to
1
T
1
Figure 6-2: Interrupted noise example
indicators with an ending RT60 time value.
2
T
2
Background
noise level
Models SE and DL