Traditional speakers do this with one or more drivers . A driver produces sound waves by rapidly vibrating a flexible cone , or diaphragm . The narrow end of the cone is connected to the voice coil . The coil is attached to the basket by the spider , a ring of flexible material. The spider holds the coil in position, but allows it to move freely back and forth.
Some drivers have a dome instead of a cone.
A dome is just a diaphragm that extends out instead of tapering in. The voice coil is a basic electromagnet . If you've read How Electromagnets Work , then you know that an electromagnet is a coil of wire, usually wrapped around a piece of magnetic metal, such as iron. Running electrical current through the wire creates a magnetic field around the coil, magnetizing the metal it is wrapped around. But unlike a permanent magnet, in an electromagnet you can alter the orientation of the poles.