Loudspeaker

A passive speaker needs an external power amplifier. A powered speaker includes amplification, so the complete product combines two functions: driving the speaker and producing sound.

For passive speakers, sensitivity states the sound pressure level produced for a specified input voltage or power at a stated distance. Compare those conditions together. Sensitivity is not maximum SPL: that is the highest sound pressure level specified under particular test conditions.

Frequency response describes output across frequencies. Read its range with the stated tolerance and measurement conditions; a bass limit at −6 dB is not equivalent to one at −3 dB.

For amplifier matching, check nominal and minimum impedance against the amplifier’s speaker-load guidance. Impedance is the electrical load presented to the amplifier and changes with frequency, so the nominal rating is not a constant value.