Hacks: Make your own aux cable

Take two old headphones and turn them into one free aux connector cable.

Tom Merritt Former CNET executive editor
4 min read
If you buy a new car, borrow a friend's, or even rent, you may be presented with a handy-dandy aux jack. Aux stands for auxilliary, it lets you hook up your music player to the car's stereo. You'll also find these ports on stereo systems, as well.

Watch this: Make your own aux cable
But to hook them up you need to buy that aux cable. They only cost around six or seven bucks, but let's say you're really cheap. I mean, there's the time to drive to the store, wait in line, etc... Even buying online has it's own hazards of identity theft. You can avoid all this hassle if you have one common problem: old, unused headphones. Here's how to make a free stereo aux cable out of a pair of old earbuds you don't use anymore. Watch our video to follow along while I demonstrate.

Ideally, the headphones still work. If they have one of the ears broken, they're not ideal, but it might be OK. Just make sure you use only cable you know doesn't have a short in it. Not all headphones have the same wires inside. Some have three, and some four. If the headphones you're cannibalizing both have the same number of wires, then you just need to match them up. If they don't...we'll get to that.

If you open up a pair of iPod headphones, you'll find four wires. Some of them are red green copper and a red-green combo. Some are red blue copper and a red-green combo. Off brands will also often have red green and copper. Red usually means right and green or blue means left. These are the wires that carry the audio. The other two wires carry the ground.

With a four-wire system, it's important to make sure the grounds are connected to the correct ground. Otherwise you don't complete the circuit and the audio won't pass through. Two three-wire headphones are easier in that way, because you only have one ground. If you're going to try hooking up three to four wires, you'll need to hook both grounds from one wire to the single ground. This is harder to make work, though.

If this is getting too complicated, you may be better off buying an aux cable. Or you can get serious and borrow somebody's continuity tester to make sure all the right currents are flowing the right way. If you go that far, you might as well just rip off the jack and wire right into that.

For the video, I used two iPod cables. Going four wires to four wires. Here's what you do.

First decided how long of a cable you want and cut the wire on both headphones accordingly.

Then *carefully* strip back the insulation. Make sure to wear protective cover.

Wire strippers are best for this, but if you're steady, you can do it with regular old scissors.

The color on the wires is a lacquer insulation. You'll want to strip it away either with a little sandpaper or just burn it off with a lighter. Either way be careful and wear protective goggles.

Heat-shrink tubing will make the wires look a little neater afterward, but a bag costs about 3 bucks. I bring it up now, because you want to put any tubing on *before* you reconnect the wires.

Twist the wires together nice and tight so they have the least chance of separating. This can be made difficult if you come across some white fibers. I just burned them off.

Now we have a choice: The quick and dirty way is to just wrap it all up with electrical tape. You may experience a lot of shorts in your connection if you do that. The sturdiest way is to grab a soldering iron--a cheap one will do for something like this--then paint a bit of solder on each wire. Let it cool. Remember that solder contains lead and you should wear proper protective coverings at all times.

If you're not using shrink tubes, THEN wrap each wire in electrical tape. Make sure to cover any part of the exposed wire where there's a short. And wrap the whole thing in electrical tape.

For shrink tubes, just bring a bit of heat on them to make them shrink. Some folks use hair dryers or lighters or even a soldering iron.

Now take it back to the car. Plug one end into the aux jack, the other into the MP3 player. And enjoy your music.

Remember, it's not just that you're saving $6.36--it's the sense of self-reliance you get from using tools and electrical tape that matters.