EARS 2

Discover the exciting world of electroacoustic music and learn to make music with sounds.

Capturing and Reproducing Sounds

Mic+Speaker

If sound is caused by vibrating objects, and every object vibrates in its own unique way, then how are headphones or loudspeakers able to play back such a diversity of sounds?

How Can Headphones and Loudspeakers Create So Many Different Types of Sound?

The secret is in the recording process, and the way in which MicrophoneA tool for capturing sound wave vibrations as they travel through the air.More infoMicrophones and LoudspeakerA loudspeaker is an instrument designed to reproduce sounds. It takes an electrical signal and coverts it in to sound wave vibrations in the air.More infoLoudspeakers work. 

Microphones come in many shapes and sizes, but in each case their job is to translate the vibrations in the air into information that can be stored.

With computers this information about sound wave vibration is stored digitally.

DSCRecord_Computer

Sound In -> Microphones

Microphones work by sensing sound wave vibrations in the air and converting these into electrical information.

Inside them they have a sensitive diaphragm that moves in response to the sound (much like the ear drum).

This movement is converted into electrical signals which can then be stored or sent to loudspeakers.

The pattern of movement will be different for each different sound wave. Microphones are sensitive to a wide range of different sound wave patterns and so can record many sounds.

Microphone

Fact

Nearly all recording today uses the properties of electricity. Electrical currents can become stronger and weaker and this property can be used to record the fluctuating pattern of sound wave vibrations.

Electrical energy (power) is usually stored in the form of direct current because an alternating current would mean that devices would repeatedly turn off and on.

Audio signals tend to be alternating currents because they have to store information about sounds, which are back and forth (alternating) vibrations.

Sound Out -> Loudspeakers

To reproduce sounds we need to be able to reproduce the soundwave vibrations made by the original object. When we imitate sounds with our voice this is exactly what we do (for example: if we imitate the sound of a passing car, or an animal).

But to recreate sounds accurately we need to be able to reproduce the soundwave vibrations in detail. Loudspeakers receive electrical signals and convert them into soundwave vibrations.

The higher the quality of the loudspeaker, the more detail of the sound wave can be recreated and therefore the better the quality of sound reproduction.

OrgangeLoudspeaker

Fact

The loudspeaker takes electrical information (the alternating current that is produced through the process of capturing sounds) and converts it into sound wave vibrations.

It produces sound wave vibrations by moving a cone back and forth (in much the same way that an object vibrates to produce sounds, see ‘Where Do Sounds Come From?‘). 

Click for MORE:

And Headphones?

Headphones are actually a special type of loudspeaker.

Instead of being on the desk or a stand in front of you, the two headphone loudspeakers are positioned directly next to your ears (one loudspeaker for each ear).

Headphones

Amplification

The boosting of a signal’s amplitude so as to increase the perceived volume and energy of the sound signal. Amplifiers may be electronic, or might be acoustic resonators (such as a guitar’s sound box).

Read more

Headphones

A pair of small loudspeakers designed to be worn directly on or in the ears.

Read more

Listening

Attention focused upon sounds.

Read more

Loudspeaker

A loudspeaker is an instrument designed to reproduce sounds. It takes an electrical signal and coverts it in to sound wave vibrations in the air.

Read more

Microphone

A tool for capturing sound wave vibrations as they travel through the air.

Read more

Recording

Recording technology allows us to capture sounds and store them so that they can be played back later.

Recorded sounds may also be edited.

Read more