Calibration Services

Laboratory reference standard microphones are condenser microphones whose mechanical dimensions and electroacoustic characteristics fulfill the requirements stipulated in the International Standard IEC 61094-1. The Acoustics Laboratory of the SCL provides calibration services on the pressure-field open circuit sensitivity of laboratory standard microphones by the reciprocity technique according to the International Standard IEC 61094-2. Both one-inch and half-inch microphones can be calibrated. Their calibration ranges are (20 Hz to 10 kHz) and (20 Hz to 25 kHz) respectively. The calibration results are corrected to the reference environmental conditions at 23°C, 101.325 kPa and 50% RH.

 

Working standard microphones are microphones whose mechanical dimensions and electroacoustic characteristics fulfill the requirements stipulated in the International Standard IEC 61094-4. The Acoustics Laboratory of the SCL provides calibration services on the pressure-field open circuit sensitivity of working standard microphones by the comparison technique according to the International Standard IEC 61094-5. The calibration ranges of varies types of working standard microphones are as follows:

1. One-inch working standard microphones: 63 Hz to 10 kHz,
2. Half-inch working standard microphones: 63 Hz to 20 kHz,
3. Half-inch working standard microphones (with CCLD preamplifier): 63 Hz to 12.5 kHz,
4. Quarter-inch working standard microphones: 63 Hz to 20 kHz.

The calibration results are corrected to the reference environmental conditions at 23°C, 101.325 kPa and 50% RH.

 

A microphone preamplifier is used with a microphone for acoustic measurements. The Acoustics Laboratory of the SCL provides calibration services on the gain, relative frequency response and input capacitance of microphone preamplifiers. The calibration covers the frequency range from 20 Hz to 100 kHz.

 

A measuring amplifier is an audio amplifier for acoustic measurements. It may be used with a standard microphone and a preamplifier to form a high precision sound level meter. The Acoustics Laboratory of the SCL provides calibration services on measuring amplifiers as per the tests for the acoustic response with different frequency and time weightings described in the International Standards IEC 60651 and IEC 60804. The calibration covers the frequency range from 20 Hz to 20 kHz.