The second main feature of musical sound – is its duration. Duration – the time during which we hear a sound. It depends on the duration of vibrations, supported by the Executive for a certain time. To record musical sounds used notes. They reflect the pitch and duration of sounds. But note only determine the relative duration of the sound, which may vary. Various works performed at a different pace, that is, at different speeds. Compliance with the exact tempo plays an important role in the transmission of the content of the musical work. Change of pace in the direction of acceleration and deceleration can completely distort the meaning of the music. Funeral March can not perform at a pace of polka. In his “Carnival of Animals” Saint-Saëns reaches comic effect in the image of a turtle. For its characteristics it uses the famous cancan melody from the operetta by Offenbach, but it turns at a very slow pace. As a result, one and the same melody makes the listener a completely different impression. Kankan is the excitement, fun, and “Turtle” – a smile.
Another property of sound – is his strength. The strength of the sound – the extent of its volume. The volume depends on the scope of the sounding body vibrations – vibration amplitude. With increase in the amplitude of sound power increases and vice versa.
To the human ear start to record the audio signal requires this level of sound energy that would cause the eardrum to vibrate. If the sound power will be less than a certain minimum, we just do not hear the sound. This minimum is called the lower threshold of audibility. There is also an upper (painful) hearing threshold, that is, the maximum sound level, above which the person ceases to feel the difference in the sound power and even feel pain. Excessive sound volume detrimental to the perception of the music. The auditory nerve by prolonged stimulation tired. This happens when we are in for a long time take a beep high volume. This natural laws of human perception is often neglected in the formulation of modern variety shows, when the music and microphone gain votes just stun his audience.
One the same melody can be sung or played on the instrument louder or softer, and this largely depends on the expressiveness of performance, the impression she would make on the audience. The most commonly used a gradual increase in sound attenuation smooth it, preserving smooth, quiet or loud sound.