Version 4

    Introducing Microphones and Speakers

    The Learning Circuit | element14 presents |  Project Videos



    Time to learn about electronics that produce and interpret sound. But before getting into the electronics, it’s good to first understand how sound works. When a sound is generated, a vibration is produced that pushes and vibrates the surrounding air which continues and is carried through the air until it reaches our ears or other devices that can interpret sound.




    Speakers are electronics that generate sound. The two main types are dynamic, which use permanent and electromagnets to vibrate a diaphragm, and piezoelectric, which use electrically charged plates that bend and flex when a charge is introduced or removed. It’s all about those good vibrations.


    Did you know that a microphone is basically a speaker working in reverse? You can even take a set of headphones and use them as a microphone. Try it some time with a set of earbuds. Since microphones are essentially speakers, they use the same types of technology to interpret sound, magnets or piezoelectric. Note from Karen: “Doing research for how things works are always extra fun when it involves taking things apart. One of my favorites was taking apart the tiny DC motors to find the little lamination and magnets inside, but speakers were a close second. It was interesting to see the slight difference between different models. And with small speakers, I couldn’t always guess whether it would use a piezo or magnets. If you’ve got a solid rotary tool handy, I highly recommend taking your components apart to see what’s inside. You might be surprised by what you find.”