Pronunciation GB: ˈæmplɪtjuːd, GA: ˈæmplɪtuːd

The extent of pressure variation above or below atmospheric pressure during the production of a sound. Various measures of amplitude are possible:

  • Peak amplitude: See 1 in the diagram below.
  • Peak-to-peak amplitude: See 2 in the diagram below
  • Root-mean-square (RMS) amplitude: This is calculated from a sampled portion of the waveform according to the formula

    where N is the total number of samples and xi is the amplitude of the i th sample