This article was taken from the June 2015 issue of WIRED magazine. Be the first to read WIRED's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online.
David Sheinkopf, director of education at New York's Pioneer Works Center for Art and Innovation, has found a way to play music through a Post-it note. "Run a current through a coil of wire, and you have an electromagnet," he says. "This pushes and pulls against a fixed magnet next to it, turning magnetomotive force into motion, which moves the Post-it and disturbs the air around it." Once these disturbances hit your eardrum, they're transformed into sound.
You'll need:
- A Post-it note
- Magnet wire
- A strong magnet (neodymium magnets are available at most hardware shops)
- Clear tape
- Alligator clips
- Male-to-male headphone cable
- Scissors
- Sandpaper
Prepare the magnet wire
Take 120cm of wire and sand away the thin enamel from the ends, so the copper underneath is visible. Wind the wire around your finger, leaving 5cm at each end. "When you remove the wire from your finger, the wire loop should resemble a doughnut with two wires hanging off," says Sheinkopf. "Use the tape to hold the shape."
Attach the Post-it note
Tape your magnet to the tabletop. "Be careful when handling the magnet as it's so strong it can jump out of your hand if there's any steel or ferrous metal nearby," warns Sheinkopf. Place the Post-it note on the table, on top of the magnet, and tape the doughnut in the centre of the paper, so it sits on top of the magnet.
Ready your head gear
Attach the alligator clips to one end of the headphone cable. "Clip a length of prepared wire to the tip of the jack and another to the next segment," says Sheinkopf. "Attach the two other ends to the magnet wires coming off your wire loop." Plug the opposite end of the headphone cable into a phone or media player.
Get the best beats
The speaker's volume is compromised by its simplicity, so for the best experience, Sheinkopf advises that you press your ear against the table. "If your ear creates an airtight seal, it should sound surprisingly good," he says. "I'd try music with a lot of volume to really make the speaker sing."
This article was originally published by WIRED UK
