ABSTRACT
Magnitude is a general term that we use for the property of a sound wave that determines the loudness that a listener experiences: Other things being equal, the greater the magnitude the greater the loudness. A measure of sound magnitude is the sound pressure amplitude of a sound wave (an alternative measure, intensity, is described briefly later). On a sound pressure waveform, amplitude of pressure corresponds to the height of the line above or below zero. Figure 10.1 (top) is a waveform of [ɑ] (like that of Fig. 8.1). Figure 10.1 (bottom) represents the waveform of a sound similar in all respects to that of the waveform above it, except that it has less amplitude. The sound represented in Fig. 10.1 (top) would be heard as louder than that represented in Fig. 10.1 (bottom). An increase in amplitude (other things being equal) produces an increase in the loudness of a sound. The term loudness is reserved for the sensation experienced by the listener, rather than sound magnitude itself, and this usage is consistent throughout the speech and hearing science literature. The relationship between loudness and sound pressure amplitude is described in Chapter 14. Waveforms of [ɑ], identical except that the top waveform has greater sound pressure amplitude than the one beneath. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203053867/9b8ca3dc-18e7-495e-9393-2a4bdcd01e4c/content/fig10_1_B.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
