Legacy AERIS Owner's Manual page 12

Amplification
When an amplifier is unable to fulfill your loudspeakers demands, a
damaging harmonic spike may be leaked to the high frequency drivers.
Another important point regarding loudness is that the dB scale is a
logarithmic one. This means that a 150 Watt amplifier will potentially sound
only twice as loud as a 15 Watt amplifier. If all of this discussion of power
and loudness seems a bit abstract, consider the example below.
The average acoustical power developed by a person speaking in a
conversational tone corresponds to a mere 0.00001 Watts. The power that
would be developed by the entire population of the city of New York
speaking at once would barely illuminate a single 100 Watt light bulb.
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