G.R.A.S. 42AB-S1 Sound Calibrator for LMS SCADAS 3D Binaural Headset

Sound pressure level: 124 dB
Frequency: 250 Hz
ANSI: S1.40
IEC: 60942

Typical applications and use

  • Microphone calibration


The 42AB-S1 consists of a sound source, a reference microphone, and an electronic control circuit. The special reference microphone is extremely stable and independent of variations in barometric pressure, temperature, and humidity. The reference microphone and control circuit together maintain a constant sound pressure level inside the calibration chamber and automatically adjust for changes in load volume, temperature, humidity, and barometric pressure.

Additionally, the calibrator will automatically switch off when the microphone under test is removed from the calibration chamber.

The calibration level is 124 dB (re 20 µPa) at 250 Hz. The output level meets the requirements of IEC Standard 60942 (2003-01) Class 1 and is therefore in accordance with international standards. It complies with ANSI S1.40 (1997).

The G.R.A.S. 42AB-S1 is supplied with a leather protection case and an individual calibration certificate.

Warranty, service and repair


Before leaving the factory, all G.R.A.S. products are calibrated in a controlled laboratory environment using traceable calibration equipment. Individual test certificate for the calibrator is included.

Performance and Warranty

G.R.A.S. products are made of components from our proven standard portfolio and are all manufactured of high-quality material and branded parts that were chosen and processed to ensure life-long stability and robustness.

The calibrator comes with a 2 year warranty.

The warranty does not cover products that are damaged due to negligent use, an incorrect power supply, or an incorrect connection to the equipment.

Service and Repairs

All repairs are made at G.R.A.S. International Support Center located in Denmark. Our Support Center is equipped with the newest test equipment and staffed with dedicated and highly skilled engineers. Upon request, we make cost estimates based on fixed repair categories.

If a product covered by warranty is sent for service, it is repaired free of charge, unless the damage is the result of negligent use or other violations of the warranty. All repairs are delivered with a service report, as well as an updated calibration chart.

Frequency Hz 250 (± 0.2 %)
Sound pressure level dB 124 (± 0.2 dB)
ANSI standard S1.40
IEC standard 60942
Temperature range, operation °C / °F -10 to 50 / 14 to 122
Battery type 9V 6LR61
Weight g / oz 220 / 7.76
G.R.A.S. Sound & Vibration reserves the right to change specifications and accessories without notice.


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G.R.A.S. Sound & Vibration reserves the right to change specifications and accessories without notice.