Cirrus Optimus Green Series, Instrument Hanbook

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Optimus sound level meter - instrument handbook
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4.6 Audio recording
Audio recording can be started manually using the audio soft key or automatically using
the audio triggers.
This starts the Optimus recording raw WAV data at a quality, which can be set in the
menu (standard, high or studio).
Details of the audio triggers can be found in Technical Note 28 - Audio Recording with
the Optimus Green sound level meters. Please refer to the Cirrus Research plc website
at www.cirrusresearch.co.uk/library/optimus.
Pressing the audio key again stops the recording. There is no maximum duration of
an audio recording set by default, but this can be changed in NoiseTools, and the
parameters for the audio triggers can be configured in NoiseTools.
The audio recording includes a 10 second back buffer (on the standard quality setting).
When triggering a recording manually, it’s very difficult to record the beginning of a
sound that catches your attention.
The back buffer will cover the time it takes you to respond and press ‘record’.
10 seconds is the default duration, which can be changed in NoiseTools.
The time history display and analogue bar turn
blue when audio recording is running
and revert to green when it has stopped.
Starting and stopping audio recordings during a measurement does not affect the
noise measurement data being recorded.
Please note, VoiceTags are recorded BEFORE the measurement starts and are for
spoken notes only, not for analysis of recorded sounds.
4.7 Timers
The single and repeat timers allow you to make precisely-timed measurements over
pre-set or custom defined durations, which are set on the instrument using the storage
options menu (see next chapter).
The repeat timer allows measurements to be stopped and started automatically over a
long period of time. The Optimus can still be stopped and started manually when the
repeat timer is active.
The repeat timer is synchronised to the real-time clock, so if you choose a 30 minute
duration, the measurement will begin on the hour and at 30 minutes past. When the
measurement ends, a new one will begin and last for the next 30 minute interval.