Compulsory for successful commissioning measurements is, that the adjustment of the subsystems in free field conditions is accurate. The generation or correction of controller setups after the equipment has been installed, is virtually impossible.
Generally the calibration starts by checking the operation of all the components (alignment, curving, amp gains, limiter, routing, polarity, backup systems). This is where most of the error sources hide, which have to be eliminated prior to the actual measurements.
At 20-50 measuring positions per loudspeaker or array the frequency response on the main axis is recorded, in large venues via a wireless system. These measurements contain any reflexion that occurs in the room and their energy average results in a representative characteristic. From this curve the EQ setting for the respective loudspeaker, also called Hauskurve, is deduced.
Afterwards the levels of all the individual systems or clusters are adjusted to each other.
Eventually from delay measurements at dedicated positions the delays of the subsystems are tuned, so that the localization of the main system (stage) remains unaffected.
The procedure is concluded with a listening test to verify the settings made.