Main characteristics of a musical sound are given below:
A musical sound has three main characteristics namely loudness, pitch and quality.
Loudness is defined as the listener’s auditory impression of the strength of a sound. In other words, it is a subjective impression related to the intensity component of sound. The sound waves falling on the eardrum of the listener produce the sensation of hearing.
The sensation of hearing which enables us to distinguish between a loud and a faint sound is called loudness. It depends upon the intensity of the sound as well as the sensitiveness of the ear of the listener.
Also, the same sound may appear to be loud to one person and faint to other. Due to this reason, it is not entirely a physical quantity.
The unit of loudness is either decibel (dB) or bell (B). The intensity of sound, and hence its loudness, depends upon the amplitude of vibration of the source, the surface area of the vibrating source, the distance of the source from the listener, density of the medium through which sound travels from the source, presence of surrounding bodies, motion of the medium, etc.
It is the characteristic of musical sound that helps the listeners in distinguishing a shrill note from a grave (dull or flat) one. A shriller sound is said to be of a higher pitch than the grave one.
The higher pitch is found to be of greater frequency and lower pitch of lower frequency. However, the pitch is not stable but changes with frequency. The voice of a child is shriller than a boy and much shriller than a man. Quality
It is the characteristic of musical sound that distinguishes between two °r more sounds of the same pitch and loudness from each other.
Quality of a sound is determined by the number of harmonic components in it. More the number of components more pleasing is the sound. The presence of different number of harmonics present in the different musical instruments helps to identify them from each other.