electricity, watt, volt etc in sound context (sound systems, amps)



electricity, watt, volt etc in sound context (sound systems, amps)

In: Technology

Speakers work by moving a cone back and forth. This pushes and pulls air, which creates sound waves. The way this is done is that there’s a permanent magnet attached to the part of the speaker where the cone is. There is also an electromagnet. By turning the electromagnet off and on, you can make the two magnets push away from each other, or pull together. This is what makes the cone move which makes the sound.

Turning an electromagnet on basically means passing a current through the coil (measured in amps) by applying a voltage to it. The strength of the electromagnet depends on the voltage applied to it (measured in volts), so basically the voltage related to the push or pull which relates to the volume of the sound.

An amplifier is used to scale a signal up or down. Let’s take an electric guitar. The metal strings vibrate over a coil of wire, the pick-up, acting like another electromagnet. This creates a small fluctuating signal in the lead. The lead takes it to the guitar amp, which turns the small (low voltage) signal into a bigger (higher voltage) one, before sending it to the electromagnet at the speaker cone.