Audio Engineering Society

ALSO CALLED: AES
DEFINITION: Pink noise is acoustical energy distributed uniformly by octave throughout the audio spectrum (the range of human hearing, approximately 20 Hz to 20 kHz). Most people perceive pink noise as having uniform spectral power density -- the same apparent loudness at all frequencies. In pink noise, the total sound power in each octave is the same as the total sound power in the octave immediately above or  … 
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AUDIO ENGINEERING SOCIETY DEFINITION (continued): …  below it. An octave is a band whose highest frequency is exactly twice its lowest frequency.So-called white noise contains sound power distributed uniformly in absolute terms. True white noise sounds like there is more treble than bass because the human ear/mind interprets sound in terms of octaves, not in terms of absolute frequency. Any given octave represents a frequency band twice as large, in arithmetic terms, as the one below it. For example, the octave from 100-200 Hz is 100 Hz wide, the next octave (200-400 Hz) is 200 Hz wide, the octave above that (400-800 Hz) is 400 Hz wide, and so on. … 
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