This is a small speaker project that can be made cheaply and with few materials. if fitted in a retro looking enclosure a retro speaker can be made that is portable and does not need batteries. The synthesizer no longer worked, and because it use to make music I fixed it in a way to make a speaker to again make music. It runs off of the MP3 players battery.
Step 1: Grab the Materials and Tools
Speaker without wires (de-solder these if necessary) I took mine from a synthesizer.
Case (again from the synthesizer) just a casing for the speaker if possible.
Headphone wire ( a wire with a 3.5 jack on the end to fit into an MP3 player or iPod)
Soldering iron and solder
screw driver( if necessary for enclosure)
Wire strippers may also be needed (however I de-soldered my wire from an old speaker system and did not need them)
Step 2: Test/ Break
You need to remove the end of the headphones or wire that doesn't have the jack on as you will be needing this end. Strip the wires. There should be two or four wires. one or two negative and positives. depending on whether you are making a mono or stereo system you may want to wire one positive to the negative and place the other wires on the terminals of the speaker.
Step 3: Wiring
Depending on whether you are making a mono or stereo system you may want to wire one positive to the negative and place the other wires on the terminals of the speaker. Play a song. If the music plays solder the wires to the speaker terminals, if the song doesn't play check the volume and try swapping the wires around. If it still does not play de-solder the wires if you soldered them and try it again.
Step 4: Casing
After the wiring and soldering is complete it would be good to put the speaker into a casing to stop an echo. Make a small hole for the wire to fit through put it on a seam to allow the wire to be removed. I put mine in a speaker casing from an old synthesizer as the speaker fits perfectly in it.