Decibels

Decibels

• The sound intensity of a normal conversation speech is around 10⁵ (ie. 100,000) times that of whispered speech.
• To easily graph and discuss these huge range of values;
  sound intensity (power) level is defined using a logarithm and is measured in decibels (dB)
  eg. Sound Intensity Level = 10log₁₀(Isound/Istandard) dB 
  which means that a 10 times multiplication in sound intensity corresponds to an additional 10dB of sound level, and an increase from sound intensity P₁ to 2*P₁ (a two times increase in power) corresponds to 10log₁₀(2*P₁/P₁)=3dB

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