Products and Services

Audiometer Calibration System


Typical users are

  • Owners of Audiometers
    • Hospitals, ENT-department (ordinary and military)
    • Hearing clinics
    • Hearing aid fitters / dispensers
  • Calibration service providers
    • Test houses / Certification labs
    • On-site calibration providers

Calibration of supra- and circum-aural and insert earphones

Free-field calibration and audiometric booth verification

Modular artificial ear systems according to standards

Dedicated audiometer calibration analyzer


The G.R.A.S. 90AA Audiometer Calibration System is configured to meet the requirements of modern audio-meter calibration. It is easy and fast to set up and control, and can be upgraded as your calibration needs change. Two standard packages are available and several options can be added, depending on the type and features of the audiometer and respective ear-phones connected.

The 90AA Audiometer Calibration System includes artificial ears for TDH-39/49 and HDA-200 and an audiometer calibration analyser.