Speak! Speak! I'm not talking to a dog, I'm talking to my speaker. Why won't it work? Maybe if I learn the physics of it, I could probably fix it. So, inside a speaker, an electromagnet is placed in front of a regular magnet. The regular magnet is fixed hard into position where the electromagnet is moveable. As electricity passes through the coil of the electromagnet, the direction of its magnetic field is rapidly changed. Meaning, that it is then attracted and repelled from the regular magnet, vibrating back and forth, creating a frequency. The frequency of the vibrations causes the pitch of the sound produced, and the amplitude affects the volume; turn your stereo up high enough and you might even be able to see the speaker move. Also, a microphone uses the same mechanics as a speaker in reverse to convert sound into an electrical signal. In fact, you can even make a pair of headphones into microphone (off topic but in case you were wondering). So, with that maybe I can fix my speaker finally. Thanks physics.