Australian Standard Specification No.1127 “Sound System Loudspeakers” Part 5. 2.
USA – IEFE Specification Standard No.219-1975
1.POWER RATING
(A) NOMINAL POWER RATING =E2/Z Watts
Test Signal: Frequency weighted white noise.
Test Amplifier: The test amplifier used has a nominal power output capability of at least four times the nominal rated power of the loudspeaker.
Test Voltage: E is a true RMS voltage.
(B) MAXIMUM INPUT POWER = E2/Z Watts
Test Signal Sine wave.
Test Frequency: The Frequency at which minimum impedance occurs above resonance.
Test Voltage: E is the true RMS voltage which may be applied to the loudspeaker continuously without thermal overload of the voice coil.
(C) MAXIMUM PROGRAM POWER
The power amplifier rating defined by nominal power rating test specified in (A).