3 - Hearing selects intervals

Summary

Introduction

We had seen how to produce steady-pitched sounds. We can now consider how the discovery of the sensations of intervals between such sounds would have come about, and some of the implications. If you are unfamiliar with traditional nomenclature, a sixth is any pair of pitches with the sensation created by CA, a fifth CG, a fourth DG, a major third CE, a minor third EG, and a second DE (and see Appendix 1).

Whether it was with panpipes, flutes, whistles or xylophones, after an initial period when people simply made pitched noises, some experimenters selected devices making pitches which created sensations of the intervals listed above; and these intervals we use in music today. People liked them; that has been the story of music ever since. It may suggest that characteristics of these artificial pairs of sounds interact in an unusual way with a hearing system. Later in this chapter – and perhaps ten thousand years later in terms of development – there is an account of the way in which the physical features of sounds which create these sensations were discovered. But the investigation of instrumental sounds only describes the physical sounds our hearing system selected. It does not describe what we hear, still less why we selected them. So the historical picture is very important.

The aboriginal process started with simple panpipe tubes which produced a random collection of pitch sensations when played, until by accident someone found that two of such tubes produce a pair of pitches which are a ‘nice’ sensation: more attractive to him than the rest, when heard in succession. It almost certainly was one of the intervals listed above. The primitive had to observe this, connect the sensation with some property of the tubes, and then randomly try other tubes and observe whether some other pairs made a nice sensation. The sensation was ephemeral and elusive. It had to be remembered to be recognised again, and fifths can occur between pairs of high-pitched and of low-pitched notes. Someone with a bundle of crude panpipe tubes gradually selected pairs and threes and fours which produced ‘nice’ sensations between them.