Calibration - Vox -01 Operating Manual

Calibration

The VOX-01, the instrument itself as well as the microphone, is calibrated before leaving the
factory. A calibration certificate is included with the device. However, it is recommended
that you carry out your own "user calibrations" from time to time, especially under the
following conditions:
• You are using the device in temperatures considerably above or below room
temperature
• You are planning to use the device again after a prolonged period of storage
• You are planning to do measurements for which a high degree of accuracy
is required, e.g. certification measurements
Compact calibrators (with Class 2 / Type 2 compliance) are available from a number of
vendors. These calibrators generate a test tone which is adaptively adjusted to a fixed, accu-
rately know signal level (usually 94.0 dB). This makes calibration relatively easy: insert the
microphone tip into the port of the calibrator, using an adapter with suitable dimensions
for the microphone tip (1/4" / 7mm). The device should now measure the nominal signal
level produced by the calibrator.
The VOX-01 is easily calibrated with any stable sound source of a known reference level. This
can be a calibrator, but a steady sound field (the level of which is measured by another,
calibrated, SPL meter) will also work.
Calibration module while measuring a 1 kHz calibration tone.
To start calibrating, apply the calibrator to the microphone, or place the microphone in a
known sound field. Then press "start." Do not worry if the reference level shown is incorrect;
you can change this after the measurement. An octave band spectrum will be shown while
the equivalent-continuous A-weighted sound level is measured. Once this measurement is
finished, the VOX-01 will show the results.
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VOX-01 Operating Manual