Loudspeaker systems function by transforming electrical energy into mechanical energy, compressing the air, and converting the motion into sound energy or pressure that people can perceive. Most speakers are comprised of a variety of different components – including permanent magnets, voice coils and bobbins, suspensions (also called spiders), diaphragms or cones, dust caps, speaker baskets, surrounds, speaker terminals, and braided wires, which work together to produce sound. Although speaker design has improved significantly over the past 100 years, the fundamental mechanisms remained the same.
In music reproduction, a speaker driver or single speaker system acts as a transducer that amplifies electrical waves from a playback source and converts them into sound waves that can be perceived by people. This is achieved through a series of components that work together to create the sound. The magnet in a speaker driver produces an electric field around the voice coil that allows electromagnetic movement in the system. The voice coil assembly, a long bundle of tightly woven wires and a bobbin, is attached to the speaker cone and creates a magnetic field when electricity flows through it. The magnetic field causes the speaker diaphragm to vibrate, and the electrical energy is converted into mechanical energy that produces sound as the cone moves. Other elements such as the speaker suspension, basket and speaker terminals help stabilize the system and hold the speaker components in place inside the box.