As with many things, it is possible to make an invisible earphone set out of stuff you may have lying around the house and materials that are easy enough to source online. For an easy-to-follow instructional video below.
The method relayed here has been taken from Frank GuYun of Instructables.com. Links to the original article have been provided. In order to follow the process completely, you’ll need to follow both his technical schematics and his instructional video. This answer will work best if you relate to it as a companion piece, or ‘checklist’ if you will.
What now follows is a step-by-step guide to making your own pair of invisible earphones.
You will need:
1x Piece of cardboard (ideally larger than your head).
2x (or more) Neodymium magnets.
50m Enamelled wire.
2x LM386 batteries.
1x Soldering iron.
1x Circuit board (and components, including headphone jack)
1x MP3 player
1x Roll of electrical tape
STEP ONE – You’ll need to acquire some small magnets (about 6mm in length and the same in diameter is best). If buying online, the best keywords to use are ‘neodymium + magnet’, as this will generate the type of magnet you will need.
STEP TWO – You will now need to make a coil necklace. For instructional reference photos of this process, click HERE. Firstly, you will need a piece of cardboard and roughly 50 metres of enamelled wire. Enamelled wire is copper wire that is coated with polyurethane. The wire necklace must be able to fit around your head. Fashion the wire ring into a necklace that fits you comfortably (and can easily be taken on or off). Then, you cover the wire with electrical tape (in order to protect it). Next, take a knife and carefully strip away the plastic tips of the wires (you’ll find out why later).
STEP THREE – You now need to source two LM386 batteries. These batteries will power the earphones. Then, you need to construct the amplifier; a schematic is linked HERE regarding what components are needed (and what goes where). The amplifier is relatively easy to construct, but requires patience and a little bit of electronics experience. Following the video is absolutely the best way to do this.
STEP FOUR – Connect the wires to the appropriate spots on the amplifier (remember when you stripped those wires? Well now you need to solder them into place). Locate the grand wire using a multimeter and attach everything to the circuit board the way that Frank does.
STEP FIVE – Place the wire necklace around your neck and the small magnet inside your ear. Then plug the device into your MP3 player and listen to some tunes!