Electricity and sound

Let’s talk about some basic things, namely, how an electricity and a sound are linked.

In the beginning a want to talk a little bit about sound and its physical basis.

Sound is a vibration of air. The higher frequency of vibration, the higher tone of sound that we heard. The different sounds consist of a mix of different vibrations — each with its own power and frequency.

Vibration can be caused by string or surface of a musical instrument. Human’s voca; ligament vibrate and force the air around them to vibrate, this air transmits the vibration further, finally it’s transmitted to the eardrum in the ear, and that one already transmits this vibration to the nerve endings. So we hear the sound 🙂

What about electricity? I think every single person saw a speaker or have a headphones. So how it works?

Inside the headphone or speaker is a membrane, it is a plate that is attached to the coil with an electrical wire. The coil is wound around a permanent magnet with a small gap, which allows it to oscillate flexibly on this membrane without touching the magnet.

There is a physical effect, which is that if a current is passed through an inductance coil
in a magnetic field , it will move. We will force the coil on the membrane to oscillate at a given frequency by transmitting a variable frequency current to this coil. And the oscillating coil will force the membrane to move, and that one — the air around it.