Created by: Eugene, Parker, Peter, Devki
This speaker is made out of simple materials that can be found in any physics classroom.
To make this speaker, you need the following:
- paper plate
- Styrofoam cup
- magnets (around 10 small ones)
- hot glue gun with glue
- AUX cord
Useful materials (not required)
- wire-stripper (or a method of stripping the wire in some other way)
- rubber band
- cardboard box
- battery or PVC pipe (to coil the wire around)
Step 1: Get an AUX Cord
- An AUX cord is necessary to connect the speaker to the music source.
- cut and strip the ends of the cord
- leave the jack unstripped
Step 2: Coil and Glue Wire
- First, strip the ends of the wire
- Coil the wire (coil it around a battery or PVC pipe)
- Glue the wire on some sides so that it doesn't fall apart
- Cut out a piece of paper in a circle
- Using a hot glue gun, glue the coiled wire to the center of the circle
Step 3: Glue the Rim of the Cup
- Using the hot glue gun, glue the bottom rim of the cup and glue it onto the cardboard
Step 4: Setting Up the Magnet
- Take the magnets and sandwich the plates so that the magnets don't move
- Make sure that the magnets are centered and the coil of wire will go around the magnet without touching the sides of the magnet.
- Place the plate on the cardboard box with the magnets sticking up
- Set up the cups
Step 5: Rubber Bands
- Cut four equal pieces of rubber bands (these will help the circle with the coil of wire vibrate/bounce, producing a better quality sound)
- Glue the ends of the rubber bands
Step 6: Almost There...
- Glue the rubber bands to the circle and cups
- Align the circle so that the coil is facing down and surround the magnets without touching them
Step 7: Connect Those Wires
- Take one end of the stripped wire and one end of the aux cord and twist them together
- Repeat step one with other ends of the wire to complete the circuit
Step 8: "Hey Ryan, How Does This Work?"
Here's the simple version, you have to hook the wires up with the aux cord to make a circuit. When the circuit is complete, the music playing device will send a current through the wire. Since it's in a circuit, it creates a potential difference, voltage drop. A fluctuating potential difference creates movements and vibrations which creates sound! The wire and the way you coil them influences the quality of speakers. The resistance, the better sound. The more loops in the coil the better sound. The tighter you coil the wire, the better sound. Keep in mind that the resistance of wire is based on the material, cross-sectional area, and length.
Alright, here's the more advanced version:
In order to turn electric signals into sounds that we can hear, we need an electromagnet- a metal coil that creates a magnetic field when electric current flows through it- inside the speaker.
In the speaker, the electromagnet is placed directly in from of the permanent magnet, the magnet that is fixed into position (this is why we glued the magnets!). The electromagnet, our coil, is mobile, meaning that it can move around.
As an electric pulse passes through the coil, the direction of the magnetic field changes, so it is repelled from the permanent magnet and vibrates back and forth.
Because the coil is made of a flexible wire, the sound is amplified, allowing it to go in the air, which allows us to hear it.
The frequency of the vibrations controls the pitch of the sounds and the amplitude controls the volume.