Magnetic material and magnetic fields surround us in our day-to-day lives, from the refrigerator magnets to the Earth’s magnetic field to the speakers in our homes, on the stage, in our cars, etc.
Why and how do speakers use magnets? Speakers are transducers of energy that convert electrical energy (audio signals) into mechanical wave energy (sound waves). Many speaker drivers utilize electromagnetism to turn the AC voltage of the audio signal into diaphragm movement within a magnetic field to produce sound.
Every amplifier (speaker) has an electrical current. When the current is changing, it produces a magnetic field. To make the cone (or panel) of the speaker move, magnets are used to create an opposing magnetic field which creates vibrations. These vibrations are the sound we hear. Speakers often contain large magnets inside of them, as a larger opposing magnetic field creates more vibrations. The larger the magnet, the louder the speaker
Magnets are a crucial component in the design of most loudspeakers because most speakers rely on electromagnetism to act effectively as transducers. Without magnets, many loudspeaker designs would be impossible.The loudspeaker driver is the key transducer element that converts audio into sound. Most loudspeaker drivers work on principles of electromagnetism and rely on magnets to work.Typically, permanent magnets are designed into the driver to interact with the speaker diaphragm’s induced magnetic field as an audio signal is passed through the driver.The diaphragm is either made of a conductive material or is attached to a conductive material. As electricity flows through the conductor, electromagnetic induction states that a coinciding magnetic field will be produced in and around the conductor.