Sound speakers and headphones

Sound (acoustic) speakers and headphones are devices for transmitting sound.

The computer has no sound output systems, so it requires audio speakers or headphones for sound reproduction.

Operating principle

Sound devices have a loudspeaker inside. The speaker is designed to convert electrical vibrations into sound vibrations that the human ear can hear.

Inside the speaker, there is a special coil with a conductor wound on it. An electric current is applied to the contacts of this coil. The frequency of the alternating current changes with the same frequency of oscillation as the music being played. By changing this frequency, the poles of the coil are reversed. The reversal of the poles makes the coil oscillate. The oscillation of the coil's magnetic poles is transmitted to the diaphragm, which pushes air in front of it, creating sound vibrations (waves).

Built-in amplifier

The amplifier in the audio device allows you to adjust the strength of the signal in the speaker. This increases the quality of the sound signal playback.

Power

Power is the main characteristic of audio hardware. It determines the volume of the audio system. For music in the background in the workplace, a speaker with 5 watts is sufficient. To use the speakers in a small room area, a power of 5 to 20 watts is required. For sound speakers used outdoors or in a large hall, the speaker's necessary power is 50 watts or more.

Audio formats

Mono-channel sound

Monaural audio uses a single channel. This channel can be played on multiple audio devices, but all devices will play one signal copy.

Stereo sound

The stereo audio uses two channels. One channel sends sound to the left speaker, the other channel sends sound to the right speaker. By controlling these signals, you can control the position of the sound. The user will hear sounds coming from different modes.

Multichannel (surround) sound

Multichannel (surround) sound

In multichannel audio playback, more than two channels are used. A specific sound mode has its own dedicated channel with a separate audio speaker.

Connection

3.5mm connector

Computers and laptops are equipped with special 3.5-mm sound card connectors, through which sound equipment is connected.

To determine which port the plug goes to, board manufacturers usually mark the connector with a color: green for headphones or speakers, pink for the microphone.

Most modern laptops and computers are equipped with a single connector that can simultaneously detect an input sound device and a microphone.

The sound quality of wired audio devices over a 3.5mm cable depends on the quality of the sound card or amplifier to which it is connected.

USB connector

The advantage of a USB audio device over a 3.5 mm connector is consistent sound quality. When using USB, the computer sends the signal in digital form; the sound device processes it internally, converts it into an analog format and plays it back.

Wireless connection

Modern models of audio devices allow the user to connect the device remotely. This is done through a Bluetooth connection.