Music
:: Music is characterized by pitch (frequency), loudness (amplitude), and quality (timbre).
:: The typical tuning note, A, has a frequency of 440 Hz.
:: The notes on a piano vary from 50 to 10,000 Hz.
:: A full orchestra puts out about 100 watts.
:: A microphone switched pressure variations into alternating electric currents.
:: To double the sound of one flute, you need ten.
x 2 =
:: We can hear 10-12 watts/m2 to 1 watt/m2
:: Typical sound levels:
0dB - no sound;
50-65dB - normal conversation;
120+dB - a jet airplane
