How to Make a Speaker Out of a Plastic Cup

Making a simple speaker out of a disposable plastic cup is easy to do. These homemade speakers make portable sound. These speakers are a simple alternative to expensive speakers sold for MP3 players and other devices that accept headphone jacks.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Two disposable plastic cups
• Speaker magnet wire (18-gauge)
• Rare-earth magnet
• Rubber cement
• Knife (for scraping/stripping wires)
• Headphone jack (with attached wire)
• Soldering iron and rosin-core solder

1. Cut a cup from the lip to the base to make a 1/2-inch-wide strip. Do this two more times so that all three strips are equally spaced out. Remove the part of the cup that remains between the three strips. Trim the strips so that they are only 1 inch long. Fan fold the three strips so that the folds are 1/4-inch folds.

2. Glue a rare-earth magnet onto the interior center of the cup that has the fan folds on it. Get one of the scraps left over from the first cup and wrap the piece of plastic around the magnet to measure the circumference. Cut the piece of plastic 1/4 inch longer than the magnet circumference. Trim the plastic strip so that it has the same width as the magnet.

3. Glue the plastic strip loosely around (but not onto) the magnet so it will slide off the magnet easily. Slip the loop off the magnet. Wrap the speaker magnet wire around this plastic loop 100 times. Leave 2 inches sticking out at both ends of speaker magnet wire for soldering. Glue the speaker wire in place with rubber cement and allow the glue to dry.

4. Glue the loop of plastic that has wire on it to the bottom of the other (uncut) cup that will form the inner speaker cone. Slip the inner cone over the fan-folded cone so that the loop slips over the magnet. With the loop lifted halfway up the magnet's side, glue the fan folds to the inner cone so that the loop is held in place. Make another speaker the same way.

5. Strip the free ends of the magnetic speaker wire by scraping the coloring off the ends to expose wire underneath. Scrape the insulation off the ends of the wires of the headphone jack. Plug in the jack and turn on the sound for the device that you will be using. Experiment with the ends of the wires until you get the right sounds. Solder the wires in place or simply twist them together and tape the connection in place.

Tips & Warnings

• Some jacks have three connections for stereo sound. There are two of the connections that need to go to different speakers and one connection that is shared and that both speakers will attach to when you are experimenting.
• Make sure that there are no shorts in the wires and that you are only hooking up the headphone jack to devices that are designed to hook up to headphones. Wear goggles during this project. Read and follow all instructions that come with the devices and tools that you are using.

References

• Styrofoam Speaker Plate
• Plastic Cup Speaker
• Speaker With Fan Fold Springs

Resources

• Soldering
• Speaker Plate