a) Bone flute from the Gudenus Cave near Krems/Lower Austria (approximately 16,000-10,000 B.C.) - currently in the Natural History Museum, Vienna.
b) Sonagram with the fundamental indicated by the color green (3.5 Khz) and the first overtone in orange (7 Khz); all other tones are the result of sounds caused by blowing. The length of the tones is indicated with orange stripes. Both curves show the nature of the sound waves for the left and right channels (stereorecording). The red curve shows the waves of the point in time that is marked by the eprovettes.
c) The development of the sound spectrum of the
wave length demonstrates at first the fundamental as well as the first and
second overtones; the other peaks merely represent the secondary noises
that occur when the instrument is blown. As the sound ends, the overtones
disappear. (E. Stadler)