About Sound Fields; Measurement Control; How To Set Up Measurement Controls; About Logging Mode - B&K 2245 User Manual

About Sound Fields

It is important that the instrument knows the type of sound field in which you are measuring so it can apply the appro-
priate correction to your measurements. Theses corrections will enhance the overall frequency response of the system
regardless of whether or not the microphone you are using is designed for the sound field in which you are measuring.
Choose Free-field if you are in an environment with no (or very few) objects or surfaces that will reflect sound.
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Free-field sounds generally come from the sound source
Choose Diffuse-field if you are in an environment with lots of objects or surfaces that reflect sound. Diffuse-field
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sounds come randomly from all angles (random incidence) due to reflection off surfaces within the envir-
onment
✐ Note: Generally, ISO requires free-field conditions and ANSI requires diffuse-field conditions. Be sure to check your
local standards for the setting you require.

Measurement Control

Measurement control settings specify how your measurements will run.

How to Set up Measurement Controls

1. Open the menu.
From the instrument: Press
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From the mobile app: Tap to open the instrument menu.
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2. Go to: Measurement settings > Measurement control.
3. Choose whether or not to log data.
If you enable Logging mode, specify a Logging interval.
4. Set Measurement time to Preset or Free.
5. Choose whether or not to back-erase when resuming a paused measurement.
If you enable Back-erase mode, specify a time in Back-erase time.
✐ Note: Back-erase will not be applied to logged data.

About Logging Mode

Logging measures and saves data periodically on the internal disk and thus creates a profile of measurement data. Meas-
urements are restarted for each interval. This is done in addition to also measuring the data for the total measurement
time.
Disable to turn off Logging mode
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Enable to save data at intervals, with the interval specified in Logging interval
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briefly to open the menu.
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Set up the Instrument: Measurement Control