The active operating principle exploits the unique combination of the 9320A headphone output with a specific 8550A headphone, identified by its serial number. Using the serial number, the headphone's unique factory calibration profile is applied by the digital signal processing of the 9320A. This active operating principle enables precise and extremely linear system output, removing unit-to-unit variations and resulting in high precision of reproduction.

The Genelec UNIO PRM solution bridges in-room and headphone monitoring by enabling the use to seamlessly transition between a calibrated SAM Monitoring system and headphone-based monitoring. This enables efficient workflows, productivity, and reliability of audio engineering work. Personal Reference Monitoring (PRM) is an active reference monitoring solution using the 9320A SAM Reference Controller and 8550A Professional Reference Headphones. This matched system enables the you to access the full content of audio and achieve the highest monitoring system.