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Additional options

Running reverberation test

Running reverberation test

There are a couple factors to consider when conducting a reverberation test. Depending on if you will be measuring voice in a room, hall, theatre (etc..), ISO 3382 standard recommends measuring reverberation time for speech from 63 HZ to 4 kHz. However for rooms with other intentions (i.e., music/acoustical concerts), one-third octave bands from 100 Hz to 5 kHz can be used/applied. ISO 3382 also recommends a minimum number of recorded studies in order to obtain a reliable reverb measurement session. This is done for two reasons: (1) because the test signal is random noise, there will be a bit of run-to-run variance. By taking a number of measurements from the same location and averaging them together, you get a more reliable estimate of the actual measurement (2) Because the acoustics in a room may vary, it is suggested to do spatial averaging

-taking measurements from multiple locations in the room and average them together to get an average measurement for the room.

Once the setup options are selected, please follow the procedures below to run and view RT60 measurements.

Reverberation (RT60) Test

1.Select setup parameters via the Reverb Time screen (see “Setting up Reverberation” above).

2.(Skip this step if threshold is set to “Auto”.) View the ambient noise in the room (the LZMAXvalue) and note the value. (NOTE: To ensure a decay curve, at least 45 dB above background noise level is recommended.)

To view the ambient sound in the room do one of the following:

(A)From the Start screen, select SLM as the measurement type and select View Current Study.

Verify that the range setting is appropriate for the level being measured. It is desirable to select the longest range that will not overload. Press Up/Down Arrows to change range. (For more details, please see “Measurement range”, page 60.)

Press Run/Pause key and notate the average level. (NOTE:

you may need to press the Look-up softkey and select Leq to view the average ambient sound level. For more information please refer to, “Changing displayed measurements”.) When completed, press Run/Pause key and then press Stop key to end the session.

(B)Follow “A” above but select 1/1 or 1/3 as the measurement type.

Models SE and DL

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3M DL, SE user manual Running reverberation test,  Reverberation RT60 Test