In music, a tone is distinguished from noise by its definite pitch, caused by the regularity of the vibrations that produce it. Any tone possesses the attributes of pitch, intensity, and quality. Pitch is determined by the frequency of the vibration, measured by cycles per second. Intensity, or loudness, is determined by the amplitude, measured in decibels. Quality is determined by the overtones (subsidiary tones), the distinctive timbre of any instrument being the result of the number and relative prominence of the over tones it produces. The ....