79

Additional options

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 T1 and T2 indicators with an ending RT60 time value.

NOTE: T1 is calculated from two reference points on the regression line to ensure an accurate sound level capture

T1

T2

Background noise level

Figure 6-2: Interrupted noise example

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.

Models SE and DL

Page 92
Image 92
3M SE, DL user manual Interrupted noise, Impulse noise