Sound has three characters.
1) Loudness
2) Pitch
3) Quality or timbre
Loudness of a sound: Loudness is the quantity of energy possessed by the sound.
The unit of loudness is bel and the practical unit of loudness is the decibel(dB). 1 decibel means \(\frac{1}{10}\) of bel. Loudness depends on a few factors.
Factors on which Loudness depends:
i) Distance between the source and the listener. When the distance between the source of the sound and listener increases the loudness decreases and when the distance between the source of the sound and listener decreases the loudness increases.
ii) Area of the sounding body. More the area of the sounding body more will be the loudness and less the area of the sounding body less will be the loudness. The loudness of the sound will be less in a small bell compare to a large bell. the sound of dhak will be greater than tabla. Because the area of sounding body dhak is greater than tabla.
iii) Presence of the resonance body. The loudness of sound is increased in presence of a resonance body.
iv) Density of the medium. More the density of the medium more will be loudness. If the density of the medium decreases loudness decreases. The loudness of the sound that passes through an iron tube will be greater than that passes through the air.
v) Amplitude of the sound wave. More the amplitude more will be the loudness and less the amplitude less will be the loudness.
vi) Flow of media current. If the sound travels through air or water in favor of air current or in favor of water current then the loudness of sound appears to be greater in the listener's ear. If the sound travels against a water current then the loudness of sound appears to be less in the listener's ear.
2) Pitch of a sound: The second characteristic is the pitch. Pitch is the sharpness or shrillness of the sound. If the sound is shriller then its pitch is greater and if shriller is less then its pitch is less. It depends on frequency. More the frequency more will be the pitch and less the frequency less will be the pitch.
That is why female sound is Shiller than mail sound. Because the vocal cord of a female is softer than a male vocal cord. So the frequency of sound made by the female vocal cord is much greater than that made by the male vocal cord. As the frequency is greater pitch will be greater. So the sound will be shriller.
3) Quality or timbre of a sound: If different sounds emitting from different musical instruments like setar, guitar, harmonium, etc having the same loudness and same pitch then we can differentiate sounds with quality. So quality or timbre of a sound is the characteristic of sound by virtue of which we can differentiate different sounds immersing of different sources having the same loudness and same pitch.
Facebook
Twitter
Linkedin