Active Loudspeakers

The basic procedure of measuring sensitivity, maximum SPL and directivity is the same as for passive loudspeakers, whereas measurement of impedance is inapplicable. Additionally any possible parameters can be determined for the individual channels, active and/or passive, as well as frequency responses of the filters of an internal or external controller.

Standard measurements for data sheets are:

Sensitivity Magnitude, phase, average sensitivity
Freq. resp. of filters Room EQ, other filters
Maximum SPL at 3% and 10% THD
Directivity horizontally and vertically

Additionally the following measurements can be included in the data sheet:

  • Sensitivity, impedance and directivity of the individual channels
  • Frequency responses of the active crossover filters and equalizers
  • THD(f) (Total Harmonic Distortion) at multiple input voltages
  • Limiter operation


Anselm Goertz