Page 38 - The Master Handbook Of Acoustics
P. 38
13
FUNDAMENTALS OF SOUND
f 1
Amplitude
0 A
Time
f 2
0 B
f
f 1 2
0 C
f 3
0 D
f f f 3
1
2
0 E
FIGURE 1-11
A study in the combination of sine waves. (A) The fundamental of frequency f . (B) A
1
second harmonic of frequency f = 2 f and half the amplitude of f . (C) The sum of f
2 1 1 1
and f obtained by adding ordinates point by point. (D) A third harmonic of frequency
2
f = 3 f and half the amplitude of f . (E) The waveshape resulting from the addition
3 1 1
of f , f , and f . All three components are “in phase,” that is, they all start from zero
1 2 3
at the same instant.
