Sonagram
A visual representation of sound, in the form of a trace on a graph, in which the vertical axis shows frequency ('pitch'), being graduated in kiloHertz (kilocycles), and the horizontal axis shows duration (in seconds). The degree of blackness or greyness of the sound trace indicates loudness ('amplitude'). The word 'sonagram' is actually an abbreviation of 'sound-spectrogram', the machine used being a 'sonagraph' or 'sound-spectrograph'. A 'melogram' (produced by a 'melograph') is somewhat similar to a sonagram but analyses the frequency of the sound much more precisely and also shows its relative intensity in decibels (so that two graphs are produced). Sonagrams, and to a lesser extent melograms, are now widely used in the study of bird song and call notes.From Peter Weaver's Birdwatcher's Dictionary
Copyright © 1981 by Peter Weaver