Telephone Transducers

you so we've used pizza discs to make contact mics which is a bit backwards because they're manufactured to make sound not to pick up the sound if we want to make a wider range of sounds in a single beep there's a little trick that we can do to turn this into what's called a transducer a device for fixing to other materials to make what you could call speaker objects in addition to the gates disk will need a small amplifier it has to be an amplifier that has an external speaker jack on it such as this little RadioShack amp if the amplifier says that it has a headphone jack there this will not work headphones are 200 ohm load or so allowed speakers 8 ohms this is tedious and boring but this has to do with the next step of this project we need a little device called an audio output transformer to the best of my knowledge the only place you can get one is at RadioShack I don't believe anyo