Speaker - SS1 ICT Lesson Note

A speaker is a transducer device that converts electrical signals into sound waves, allowing us to hear audio content such as music, speech, and various other forms of sound. Speakers are a fundamental component of audio systems, ranging from simple devices like those found in smartphones and laptops to complex setups in home theater systems, concert venues, and more.

 

 

Source:(becomesingers.com)

 

Structure of a Speaker:

A basic speaker consists of several key components:

1. Cone (Diaphragm): The cone, also known as the diaphragm, is a thin, flexible material (usually made of paper, plastic, or other lightweight materials) that moves back and forth in response to electrical signals. This movement generates sound waves.
2. Voice Coil: Attached to the back of the cone is the voice coil, which is a coil of wire suspended in the magnetic field of the speaker's magnet. When an electrical current passes through the voice coil, it interacts with the magnet's field, causing the coil and the attached cone to move.
3. Magnet: The magnet creates a magnetic field that interacts with the voice coil's current, resulting in the movement of the coil and the attached diaphragm. The strength of the magnet and its interaction with the voice coil determine the speaker's efficiency and response.
4. Suspension System: Surrounding the cone is a suspension system that allows the cone to move freely while maintaining its proper alignment. The suspension system typically includes a flexible material that provides support and helps center the cone.
5. Frame (Basket): The frame, also known as the basket, holds all the components of the speaker in place and provides structural support.

 

Function of a Speaker:

The primary function of a speaker is to convert electrical signals (representing audio content) into sound waves that can be heard by humans. Here's how it works:

1. Signal Input: An electrical audio signal is fed into the speaker through a wired or wireless connection.
2. Voice Coil Movement: The electrical current passing through the voice coil generates a magnetic field. This interaction between the coil and the magnet causes the coil (and the attached cone) to move back and forth rapidly.
3. Sound Wave Generation: As the cone moves, it compresses and rarefies the air in front of it, creating areas of higher and lower air pressure. This movement of air pressure results in the generation of sound waves.
4. Sound Emission: The sound waves produced by the movement of the cone travel through the air as pressure waves. These waves reach our ears, where they are detected by the eardrums and interpreted by our brain as sound.

 

Types of Speakers:

1. Full-Range Speakers: These speakers are designed to reproduce a wide range of frequencies, from low to high. They are often used in compact audio systems, computer speakers, and car audio.
2. Subwoofers: Subwoofers specialize in reproducing low-frequency bass sounds. They are commonly used in home theater systems, car audio setups, and music production environments.
3. Woofers: Woofers handle mid-range and low-frequency sounds. They are often found in larger speaker systems and contribute to the overall richness of audio.
4. Tweeters: Tweeters are responsible for reproducing high-frequency sounds, including vocals and instruments like cymbals. They enhance the clarity and detail of audio.
5. Mid-Range Speakers: These speakers focus on reproducing mid-range frequencies, making them suitable for vocals and many instruments.
6. Multi-Way Speakers: These speakers combine multiple drivers (such as woofers, tweeters, and mid-range drivers) to cover a broader range of frequencies, resulting in more accurate and balanced sound.
7. Coaxial Speakers: Coaxial speakers combine multiple drivers in a single unit, often placing a tweeter at the center of a woofer. This design helps with better sound integration and dispersion.
8. Component Speakers: Component speaker systems separate drivers (such as tweeters, woofers, and mid-range drivers) to allow for optimal positioning and customization.
9. Active/Powered Speakers: These speakers have built-in amplifiers, which means they can be connected directly to audio sources without needing an external amplifier.