All G.R.A.S. microphones are calibrated as an integral part of our quality assurance. This calibration is traceable to the National Physical Laboratory (NPL) in England. It is performed by specially trained G.R.A.S. personnel under controlled conditions and according to established procedures and standards.
We also offer Traceable Calibration as an after-sales service – this is the same rigorous calibration that is the final stage of our quality assurance.
New as well as re-calibrated microphones are delivered with up-to-date calibration information on individual calibration charts or extended calibration certificates, stating the sensitivity, the frequency response, and the environmental calibration conditions.
How to order - read more here.