INTRODUCTION
1
This compact sound level calibrator is a
portable, battery operated sound source,
suitable for many portable sound level
meters. When a microphone from a sound
level meter is inserted into this calibrator,
the sound level meter picks up the signal
and displays the signal in dB (decibel) units.
The sound level meter should be adjusted
(if necessary) to match the calibrator's
output signal as closely as possible.
This calibrator provides a stable reference
level across changes in many environmental
conditions. Corrections for variations in
atmospheric pressure are not required.
The system emits the signal through the
microphone cavity. An outer capillary hole
balances the chamber static pressure
protecting microphones from overpressure
due to their insertion.
The generated sound pressure level is
equal to 94dB, 104dB and 114 dB at 1000 Hz
frequency. The 1000 Hz frequency allows
calibrating sound level meters with any
frequency weighting (LIN, A, B, ...), Wi thout
applying any correction factor. The generated
sound pressure level is independent of
atmospheric pressure, users don't need to
adjust the value according to static pressure
over a wide range of values.
It can be conveniently used both in laboratory
and in the field. The 114 dB sound level
allows performing calibrations even in high
background noise environments.
There are total 4 models allow calibrating
different size microphones with
mechanical dimensions compliant with
IEC 61094-1and IEC 61094-4.
