The steps it took us to create our own headphones.
Step 1: Materials
32 gauge copper wire
Paper cup/ foam cup/ plastic cup
3.5 mm stereo jack AUX Plug
4 Neodymium Magnets Sharpie Sand paper
Step 2: Explanation
You need to sand the wires because the red enamel on the copper wire is an insulator. We want the wire to be a conductor so we sand the red enamel to uncover the copper coil. We chose 55 coils because the audio worked best out of 45 and 65 coils. The sound was the loudest and clearest. It was not as fuzzy sounding as the rest of the trials were. The temporary magnet which is the voice coil (aka the copper wire) is then able to work because the permanent magnet, then attracts and repels the voice coil, allowing the voice coil to produce vibrations which our brains register as sound.
Step 3: Explanation
We need a permanent magnet because it is the thing that attracts and repels the voice coil that then vibrates and produces sound. The permanent magnet must be in the center surrounded by the voice coil because the right hand rule says that the magnetic field is stronger when you coil the wire. To match that magnetic field you have to have the magnet in the center of the voice coil. While testing different number of magnets, we found that 4 magnets produced the best quality sound. The sound was not that loud but it was much clearer and you could tell the difference that 2 magnets made and 4 magnets made. We found that a foam cup worked best as the diaphragm. The paper cup produced an ok sound but the volume was very low. We found that the foam cup produced a louder sound but in terms of how fuzzy the audio was, it remained the same as the paper cup. To build this speaker, we put 2 magnets on the inside of the cup and 2 magnets on the outside of the cup. After that, you will get your coil of wire and put it over the magnets on the outside of the cup (as seen in photos). Once you add both of the coils onto two separate cups you are going to solder an end from each of the coils together. You will get the other ends and wire them through an aux plug. You will see two holes, one fore each wire end.You want to make sure that the wires do not touch because that will affect the sound of your speaker by cutting off the audio.
Step 4: Explanation
To connect wire to an aux plug terminal, you first want to sand the very ends of the wire that you’re using so that the insulator on the wire is removed. Once you are done sanding, you will have to attach the ends of the sanded down wires onto the terminals. To do this you will grab a wire end and put it through one of the holes and loop it (twist it so it is secure) Next, you will get the other wire and loop it through the other hole. You want to make sure that both of the wires and their terminals are not touching. Sound waves are produced by alternating current. When the voice coil is being repelled and attracted by the magnet, the magnet is producing alternating current. The magnet is basically switching its negative and positive side which causes the voice coil to repel and attract/ move towards and away from the magnet. Alternating current is important because it was makes the voice coil move. Without the voice coil moving, no sound would be produced through speakers or headphones. From adding and removing the number of magnets, we increased the magnetic field which produced better sound. With four vs, 2 magnets, the four magnets produced a clear sound when there was no base.
The base was very fuzzy but it was still audible.
-We chose to play softer songs with the same tone throughout the whole song so we didn’t notice of high pitches were able to be heard.
-We also tried out a song with a powerful base.
With two magnets the song with the powerful base was almost inaudible.
-Once we added two more magnets, the base became more clear.
Step 5: Troubleshooting
When we started to create our prototype with headphones it took us a couple of tries to get them to work because there were some simple mistakes that we were making during the process. The first thing you could modify when designing your headphones if they are not working is to check if your voice coil is wrapped tightly enough to make the temporary magnet have a stronger current. Also if you are not hearing much sound because it keeps on cutting off them you should try re-sanding the edges down because there could be a chance that there is still some coating on the wire blocking the current from connecting to the aux plug. Lastly if your music is still being cut off try holding the wires so they aren’t touching each other because that will also mess up the current.
Step 6: Flawless Procedure
1. Gather all materials listed above in materials section
2. First, mark where there is 15 cm on both ends of the copper wire
-Once marked, mark 5 cm and sand it down so that the wire is no longer red but a rose gold color
3. After you are done sanding, start to wrap or coil the wire around a marker (sharpie) ]
-Coil at least 55 times or more
4. Once you are done coiling, remove the wire (slide it off of the marker)
5. Cut small pieces of tape and tape the sides of the coiled wire so that it does not unravel.
6. After that get 2 magnets, put one inside of the cup and one on the outside of the cup on the bottom. Put the coil on top of the magnet on the outside of the cup.
-Tape the coil down
7. Wrap the loose ends of the wire to the aux.
-Make sure the wires are not touching each other
8. Finally, stick aux plug into headphone jack.
9. Repeat process 6-8 but change the amount of magnets each trial (by two)
10. Repeat coiling process as well for each new trial (increase/ decrease number of coils)
11. Make two speakers
-To put speakers together you will solder 1 end of each of the wires together.
-After that, you will wire one end from of the coils into the aux plug holes and solder them there as well.