IEC 60268-5(2003) Sound system equipment Part 5 Loudspeaker
20.3 Characteristic sensitivity in a stated frequency band
20.3.1 Characteristic to be specified
The sound pressure output shall be specified in a stated frequency in accordance with 20.1.1,
referred to an input power of 1 W and to a distance of 1 m on the reference axis.
20.3.2 Method of measurement
Measurements shall be made in accordance with 20.1.2, and they shall be referred to voltage
Up corresponding to a power of 1 W, where Up is numerically equal to the R value and
where R is the rated impedance.
20.4 Characteristic sensitivity level in a stated frequency band –
characteristic to be specified
Twenty times the logarithm of the ratio of the characteristic sensitivity in accordance with
20.3.1 to the standard reference sound pressure (20 μPa) shall be specified expressed in dB.