There are calibration methods as follows.

1. Perform calibration while recording via A/D conversion unit.

Perform calibration by using calibrator and our measurement units (DS series, Sound Level Meter (LA-3000), Data recorder (DR-7100) or OSRECO (recording function)).

２. Perform calibration in the OS-2000 after importing the data.

Refer to following FAQ

"How to direct input the sensor sensitivity"