harmonics. The fundamental frequency f 1 is the frequency of the first harmonic; the
frequency f 2 2f 1 is the frequency of the second harmonic; and the frequency fn nf1
is the frequency of the nth harmonic. Other oscillating systems, such as a drumhead,
exhibit normal modes, but the frequencies are not related as integer multiples of
a fundamental. Thus, we do not use the term harmonic in association with these types
of systems.