In the introduction I talked a little about how tones are produced, but of course this is only half the picture. For tones to be used in communication, they must also be perceived by the hearer, and not just as musical pitch, but as linguistic objects. Successful perception is also the first prerequisite for tonal acquisition, and that is the reason for combining in this chapter two apparently unrelated topics, perception and acquisition. I will begin with adult perception and then move on to the child. On adult tone perception, one of the most useful references is the excellent survey in Gandour 1978, still useful as I write this text.

Adult tone perception

Fundamental frequency, pitch and tone

I begin by reminding the reader of the difference between fundamental frequency (F0), pitch, and tone, already discussed in chapter one. In this order, the terms move from a purely phonetic term, F0, to a truly linguistic one, tone. F0 is an acoustic term referring to the signal itself: how many pulses per second does the signal contain, measured in Hertz (Hz) where one Hz is one cycle per second. The next term, pitch, is a perceptual term. What is the hearer's perception of this signal: is it heard as high or low, the same pitch as the previous portion of the signal or different? The mere existence of F0 differences may not be enough to result in the perception of pitch differences.