ABSTRACT
This chapter explores the acoustics of musical notes, which are perceived as having a pitch, and the psychoacoustics of pitch perception. It considers the acoustics and psychoacoustics of different tuning systems that have been used in Western music. The development of harmony in Western music can be viewed in terms of the decreasing musical interval size between adjacent members of the natural harmonic series as the harmonic number is increased. Hearing harmony is basic to music appreciation, and in its basic form, harmony is sustained by means of chords. Music can be played in all keys when equal tempered tuning is used, as all semitones and tones have identical frequency ratios. Many tuning systems were experimented with to provide tuning of thirds and fifths that were close to just tuning in some keys at the expense of other keys, whose tuning could end up being so out-of-tune as to be unusable musically.
