Sound+and+Music

Sound. What is sound? Sound is produced when the vibrations of an object make a medium vibrate (water, air, etc.). The vibrations in air are the Traveling Longitudinal Waves, these ones we can hear. Sound waves have areas of high and low pressure called compressions and rarefactions. The diagram below shows a traveling wave. The shaded bar on top represents the changing pressure. One wavelength is highlighted in red.

The wavelength of voice is about 1 meter. The wavelength and speed of the wave determine the pitch, or frequency of the sound. Wavelength frequency and speed are related to the equation: Speed = wavelength*frequency. The longer the wavelength, the lower the pitch. The height if a single wave is called the amplitude. The amplitude determines how loud the sound will be.

When two waves meet, there can be two possible types of interference; destructive and constructive. Constructive is when two waveforms add together. The peaks add with the peaks, and the troughs add with the troughs. Destructive interference occurs when the two waveforms are out of phase and the trough of one wave lines up with the crest of the other wave and vice versa.



Overtones are frequencies other than those fundamental frequencies that exist in musical instruments.