Beats by Kristine and Karylle
Step 1: Step 1: Gather Materials
-4 Plastic cups, any size (to use as a diaphragm)
-28 AWG wire (to use as a voice coil/temporary magnet)
-Sandpaper (to expose the wire)
- One roll of electrical tape (to use as a spider, or the part of the headphones that keeps the voice coil in place and make it vibrate only up and down)
-6 neodymium magnets (to use as a permanent magnet)
- 3.5 mm stereo jack (aux cord) and covering for aux plug
- Phone or ipod (audio source)
-Wire cutters (to cut the wire, tape, etc. If you don’t have wire cutters, use scissors)
- Whiteboard marker (to wrap the wire around)
- Post-it notes (so that you can take the wire off easily)
-Decorative tape(to hide the bare wire)
-Optional: Solder iron
Step 2: Step 2: Sanding and Coiling
Coiling is also necessary for making headphones. Coiling wire makes its magnetic field stronger because it increases the magnetic strength. Before coiling the wire, make sure you have at least 15 centimeters hanging off of each end, that will later connect to an aux plug.
After coiling the wire, you then need to sand about 2-3 inches of it. Sanding is necessary for making the headphones. The wire has an enamel around it, and current is not able to pass through, unless it’s sanded. By sanding the wire, you are sanding off the insulator, allowing current to flow through. We chose to have 66 coils in our headphones because the more coils you have, the stronger the magnetic field. We found that when we had over 60 coils, the sound had an exceptional amount of clearness and loudness. We settled on 66 coils because we didn’t want to have too many coils, making it hard to tape down, but we also wanted at least 60. We also tested headphones with 46 and 56, and we found that the headphones with the 66 coils produced the clearest and best sound.The coiled wire also acts as a temporary magnet, or a magnet that needs current to become magnetic. As you are coiling, make sure they don’t overlap. Overlapping the coils make it harder to take out. The ends of the wire have to be sanded to allow electric current to flow through another conductor, whether it is a wire or a terminal. In this complete circuit, the audio source acts as a voltage source, the wire acts as a conductor, and the acts as a resistor. The audio source serves as the battery and the wire has to be connected to an aux plug because it completes the circuit. Sound waves are produced when the voice coil vibrates. It vibrates because the alternating current attracts and repels to the magnets, and that attraction and repellence causes the coil to vibrate. Alternating current flows through the wires. It causes the voice coil to be a temporary magnet (a magnet that needs electricity to function), and changes the magnet’s poles. This then causes the voice coil to attract and repel to the permanent magnet (magnet that doesn’t need electricity to function, basically what you would think of as magnets. Examples: refrigerator magnets, magnets in fishing toys, etc.). When playing music through our speakers, we noticed that the bass and drums in a song were the most static and unclear sounding, though the higher notes and lyrics were very clear. We also noticed that songs whose singer had a deeper voice sounded fuzzier.
Step 3: Step 3: Magnets
After coiling, get the magnets and the cups. Put the magnets in the middle of the cup and then put the coil around it. After placing the magnet and the voice coil, use electric tape to cover and secure the voice coil and magnets. You then need to take one of the ends of the wire and thread it through the aux plug terminal. Twist the wires so that they wrap around each other, like the picture below. You can also wrap one of the wires around the metal hook once on the aux cord. This improves the clearness of the sound. However, only one of the bare, sanded wires can be touching the metal. If both are touching the metal, this will create a complete circuit, which means you will not get any music.
A permanent magnet needs to be in the center of the coil so that the coil has something to attract and repel to when the alternating current passes through it. According to the right-hand rule, the force from the inside of the armature or coil has to be pushing outwards, so the force has to come from the center of the armature/voice coil. We also decided to use 6 magnets because we wanted to use as many as possible, while not overflowing the space we had inside our coil of wire. Lastly, we decided on using a plastic cup because it produced the loudest and clearest sound.
Alternating current is needed to produce vibrations. This is because the alternating current flows through the voice coil, making it a temporary magnet. The alternating current changes its poles, making it attract and repel to the permanent magnet.
Step 4: Step 4: Decorate, Plug, and Play
After creating 2 of the headphones, you connect the 2 ends that are not wrapped around the aux plug terminals. They can be adjusted depending on how you want your headphones to be, whether they would be on your head like a headband, or under your chin. If the wires need to be longer, get more wire, and cut to the desired length. Sand the ends of the wire and wrap one of the ends of the new wire around the end of one of the connected wires. After that, you need to thread your wires through the aux plug cover and wrap them around the aux plug again. Place about a centimeter of electric tape on the wrapped wires and screw the cover on the aux plug. You can then need to wrap the headphone wires around the headband, adjusting the length as needed. Using decorative tape, or other decorating materials of choice, assemble the headphones to look as desired. Cover any exposed wires or magnets, and cover the aux plug. Plug into the audio source and enjoy listening to your music!
Step 5: Step 5: Troubleshooting
The headphones might not work the first time. If they don’t, try these:
Sanding the ends - Most of the time, the main problem is just the ends of the headphones not being sanded as good as it should be.
Different audio source-Using the headphones with a computer produced a louder sound, compared to a phone.
The amount of magnets/magnet strength- It’s best to fit as many magnets as possible inside the interior of coiled wire, because more magnets produces better quality sound.
Coil amount-The more coils you have, the louder, and clearer your speaker will sound.
Separate the bare wires- If the bare wires hanging from the coil are touching on the aux plug, sound will not be produced.
Diaphragm material- We found that although many materials worked, plastic worked best for producing clear and volumized sound.