Have you ever been at a house party when a drunken reveler tips awkwardly and dramatically into the speaker system, causing them both to crash down to the alcohol-soaked floor? Without any beats blaring, your party is doomed, right? Wrong: Head to the kitchen, grab some equipment and a packet of potato chips, and you’ve got yourself the makings of a working speaker.
As reported by Popular Science, you’ll need to first gather your decidedly low-tech equipment: 7.5 meters (25 feet) of 30-gauge magnet wire; two 0.75-inch-diameter-by-0.25-inch cylindrical refrigerator magnets; two 0.5-inch-by-1.5-inch cardboard strips; a wooden cutting board; one 6-inch-long, 0.75-inch-diameter dowel; some sandpaper; a hot-glue gun; and most importantly of all, your potato chips – thick-cut chips work best. The flavor probably isn’t relevant here.
Now, grab your magnetic wire and wrap it around the dowel to make a 1-centimeter-tall (0.4-inch-tall) coil, while leaving 30 centimeters (12 inches) of wire on each end. Add some hot glue to the coil and after it’s cooled, slide the magnetic coil off the dowel. Use your sandpaper to remove about an inch’s worth of paint at the end of the wires, and voilà: the voice coil component is complete.
To assemble the speaker segment, fold the cardboard strips into a Z shape, and glue the magnets and strips to the cutting board, before gluing the coil to a thick-cut potato chip. Glue a cardboard strip to both sides of the chip, and position the coil over the magnet.
Next, connect the speaker wires to a home entertainment system or a guitar amp, and rock out using your tiny, somewhat edible speaker! If you’ve eaten all the potato chips, there is a paper plate alternative:
Speaker systems are much more advanced these days than the original – developed in 1921 by two scientists using basically the same pieces of equipment you used here – but the operating principle is essentially unchanged. A piece of wire is wrapped around a permanent magnet, and an electrical current is passed through it, creating an electromagnet.
As alternating frequencies of current are passed through the wire, it is variably attracted or repelled from the permanent magnet; this movement pushes and pulls the speaker’s cone, and it’s these vibrations that cause sound waves to be transmitted through the air.
[H/T: Popular Science]