Lecture1 – Sound, Characteristics of sound

sound – lekcia1  – the pdf file

and the presentation

So,

the important points:

What is necessary to have a sound, respectively, the feeling for such phenomenon?

1. vibrating unit;

2. Environment in which these vibrations spread;

3. Someone perceiving the vibrations.

Definition for sound:

Sound – it’s the feeling, caused by the vibration of a flexible body in versatile medium.

Next, the characteristics of sound:

The main characteristics are four.

1.The first characteristic is the frequency of vibrations. This is the number of vibrations per second. It is measured in Herz (Hz).

the range between 20 Hz and 20 kHz- the range of frequencies we can hear.

2. The second characteristic of the sound – it is the amplitude of vibration, respectively. sense of volume.

We hear the sound pressure levels. They are measured in decibels. 0 dB is the threshold of hearing.

The human ear can perceive sound pressure levels from 0 to about 140-150 dB

3. The next characteristic of the sound – it’s duration.

It is measured in seconds of parts of the second.

4. And the fourth – this is the timbre.