LEVEL HEADED - EL WIRE HEADPHONES

Here are a couple videos demonstrating Level Headed -- EL Wire Headphones that react to the music you are listening too! The first shows the headphones decorated with EL wire and the second shows just the headphone cable decorated. Unfortunately, the camera doesn't show the correct colors and blurs them together. It looks great in person.






This instructable will show you how to decorate a pair of headphones with electroluminescent wires (EL wire) that react to the music. This project uses over the ear headphones, EL wire, an inverter taken from a T-shirt EL panel graphical equalizer display (T-qualizer knock-off), and an mp3 player. I call this project "Level Headed" because it dynamically displays the levels of the audio you're listening to on your headphones.

Materials and Tools
over the ear headphones
5 strands of EL wire
inverter
7x1 ribbon cable
7x1 crimp terminal housing
21 female crimp terminals (order extra in case you mess up)
220 ohm resistor
3.5 mm stereo cable with a male connector (cut a cheap loopback cable in half)
3.5 mm stereo splitter
electrical tape
clear heatshrink tubing
super glue
crimper or pliers with knurled jaws
soldering iron
solder
knife (for removing phosphor)
xacto knife (for cutting PCB traces)
small phillips screwdriver (for disassembling the inverter)

Step 1: ATTACHING THE EL WIRE

There are many varieties of musically sensitive EL panel T-shirts. The one I have looks like a graphic equalizer display with five different levels. Since the T-qualizer is meant to display levels, the line which represents the lowest level will stay on more often than the line representing the highest level. For the remainder of the article I will use line and level mostly interchangeably. You should keep in mind how often a line stays on compared to the other lines when choosing which color to assign to a line. To get a signal level meter effect I chose to use blue, green, white, yellow, and red EL wire. There is no reason why you can't use different or fewer colors, but every line needs an EL wire connected to it.

To connect the EL wire to the inverter I simply copied the same type of connector used by the EL panel. This connector uses ribbon cable with female crimp terminals in a 7x1 housing. The downside to this approach is that all of the EL wires have to be together where they meet the ribbon cable so that the corona wires can share the common connection. If each EL wire had an individual common connection then the ribbon cable could be split and the EL wires separated. This would allow two EL wires to be used on opposite ends of the project without wasting EL wire to cover the distance from the shared common to the desired location. Since the EL wires will be grouped together in my headphone decorations the shared common is preferable. If you'd like to use the individual common technique then you'll need to rewire the inverter with a ribbon cable that has ten lines, with common connected to every other line.

My EL wire came pre-stripped, but I did have to scrap the phosphor off the core wire. The picture above shows a razor blade, but I think a regular pocket knife works better for removing the phosphor. Here's a link to a tutorial on EL wire which includes instructions on how to properly strip it. Please read it if you aren't familiar with how to work with EL wire. The main takeaway is to be careful not to cut the corona wires when removing the insulation and to run the inverter only when the EL wires are connected. I used electrical tape to isolate the core wires once they were soldered to the ribbon cable. You will probably have an easier time with heat shrink tubing. Then I hot-glued the soldering to insulate the corona wires/common and core wires. This made a nice, rigid connection. You may want to use a large piece of heat shrink to insulate the connection while preserving more flexibility than you get from hot glue.

To construct the connector, first examine a single female crimp terminal. The set of tabs at the edge are meant to wrap around the wire's insulation. The other set of tabs near the middle are meant to contact bare wire. Insert one strand of ribbon cable in to the connector to determine how much insulation you should remove. Remove that much insulation. Reinsert the wire and line it up so that the tabs will grab the proper part of the wire when they are crimped. Normally a crimping tool is used to press down the tabs but you can use pliers with knurled jaws to do the same thing. Here's a link to a very detailed article explaining how to attach female crimp-on terminals. Once all the terminals have been attached you can insert them in the housing. The terminals have a metal catch that springs out when it reaches the hole on the side of the housing. Therefore you should make sure all the terminals are facing the same way, that you insert them into the housing the proper way, and that you insert them far enough. Wrap some electrical tape around the housing to insulate any exposed metal since EL wire is driven by high voltage that can shock you.

Comments

[electrosapien]

xMc Squidx - I'm working on a similar project and received this smaller inverter, as well, from DX. While it drives the included EL panel well, it seems to be under-powered for a project of this size. The North American distributor for the popular equalizer t-shirt company has told me they are phasing out the model used in this Instructable, they still have a few around but you have to ask for them specifically. Currently waiting on my replacement. They and other suppliers now have a red 4XAAA battery pack that works well, is very sound reactive and bright, but with no input jacks and they only drive four channels.

[xMcSquidx]

I bought the inverter you linked to in order to replicate this fine project but they seem to have updated the PCB since then. The new revision is much smaller. I think I can still pull this off but I'm having trouble figuring out what is the same and what Isn't.

[clgst14]

Could you give a link to the website you bought all the stuff? I'm not american or something so names of markets will not work..

[altosax64]

how much did this cost you?

[yardleydobon]

Around $35 to $40.

[whipflash191]

Could you clarify the headphone cable part a little more. Mainly connecting them to the inverter.

[yardleydobon]

The headphone cable isn't connected to the inverter. The EL wire wrapped around the headphone cable is connected to inverter's ribbon cable. The inverter has its own male phone connector, so you could use a different audio source to drive the EL wire than what you are listening to on the headphones. This picture shows all the connections.

[thankyouforthevenom]

ok this is actually pretty cool i might actually do this

[Br4nd0n32]

I would buy these!

[yardleydobon]

Cool, thanks. Vote for me please!

[M0HIZ]

This would be great for use when you're walking along the road at night to show other road users that you're there. You could use it on a bike helmet too.

[osgeld]

Thats pretty cool

[yardleydobon]

Thanks. Please vote for me!