The Distinction Between [æ] and [ɛ]: A Problem in Acoustic Analysis
Leigh Lisker · Language · 1948
With the development of the sound spectrograph there is evidence of renewed interest on the part of linguists in the possibilities of defining in physical terms the elements that linguistics sets up by essentially different criteria. The spectrograph has many obvious advantages over other instruments at the disposal of the investigator of speech. It yields a continuous picture of the frequency–intensity relations over a time interval of about 2.4 seconds, and performs this analysis in well under five minutes. Moreover, it obviates the necessity of relying on the results of laborious and time-consuming analyses of speech sounds originally produced subject to various ‘unnatural’ conditions. The rapidity with which the instrument operates makes it possible to deal with large quantities of analyzed material, while its ability to handle rapidly changing sounds makes it unnecessary to restrict one's study to sung or artificially prolonged vowels, or to regulate the level of pitch or intensity (loudness) at which the sounds to be studied are produced.