DIY Round Horn Speaker

Make a DIY round horn speaker using some magnets, wire and a funnel.

Horn speakers were invented in the 1880s by Thomas Edison and were perfected by Magnavox and Victrola until the 1920s. Horn speakers do not use electricity. Although they do amplify sound, they could not generate sounds compared to electrical-driven speakers of today. If you want to make a round horn speaker yourself, adding a round device such as a funnel amplifies the sound further than the general horn speaker.

Things You'll Need

• Paper
• 1-inch Neodymium magnet
• Tape
• Styrofoam plate, 6-inch diameter
• Rubber cement
• AWG 30 magnet wire
• Pliers
• Wire cutter
• Fine-grit sandpaper
• Mono audio plug
• Electrical tape
• Plastic funnel, 12-inch-diameter mouth
• 3-by-3-inch cardboard piece
• Scissors
• Utility knife
• Hot glue gun

Instructions

1. Wrap an 8-by-2-inch piece of paper around the outside of your neodymium magnet. Tape its end to its base. Wrap a 1 1/2-by-8-inch piece of paper around the outside, and tape its end to the base of the first piece of paper.

2. Glue the cylinders to the center back of a 6-inch-diameter Styrofoam plate, using rubber cement. Let the rubber cement dry for 30 minutes.

3. Wrap AWG 30 magnet wire around the outside paper cylinder. Wind around the cylinder at least 70 times. Remove the magnet wire and inside paper cylinder, using pliers.

4. Cut the wire with wire cutters and place the ends of the wire on the outside of the Styrofoam plate. Sand the ends of the magnet wire using fine-grit sandpaper to expose them.

5. Connect one end of the magnet wire to the center of the mono audio plug. Connect the other end of the magnet wire to the end of the mono audio plug. Tape the magnet wire around the center and end plugs, using electrical tape.

6. Measure the diameter of the tip of the funnel. For example, the tip of the funnel has a diameter of 2 inches. Cut the cardboard square to the dimensions of 3-by-3 inches, using scissors. Cut a 1/4-inch indention in the side of the funnel tip, using a utility knife. The speaker wires go through the indention.

7. Cut a cardboard square that is larger than the tip of your funnel. Glue the magnet to the center of the cardboard square, using a hot glue gun.

8. Insert the Styrofoam plate on the inside of the funnel. Glue the outside edges of the plate to the inside of the funnel, using a hot glue gun. Let the glue dry for 10 seconds.

9. Pull the wires from the back of the plate through the indention in the mouth of the funnel. Insert the magnet into the paper cylinder and glue the cardboard square to the outside edges of the tip of the funnel. Insert the mono audio plug into your music device.

Tips & Warnings

• Adjust the diameters of the Styrofoam plate and funnel to your desired size.

References

• Edison Tech Center: History and Types of Loudspeakers
• "Make Magazine": Styrofoam Plate Speaker

Resources

• Full Range Driver: DIY Speakers