Retrofitting Vintage 1920's Headphones With Modern Sound

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Intro: Retrofitting Vintage 1920's Headphones With Modern Sound

I was at the local flea market recently and happened upon a vendor selling vintage headphones for $5 and ended up picking up three pairs on a whim. My original intention was to adapt them to work with modern systems, but I soon found out that, after nearly 100 years, the magnets were no longer magnetic, and so I figured I would completely retrofit them with modern audio. Now the problem I ran into is that most, if not all full size modern headsets use speakers that are too large for the housing on an old pair of Brandes headphones. I then considered ear buds, and found that they do work, just not very well, so I tracked down a pair of wrap around the ear type phones, at the local dollar store, which seemed to fit the criteria for what I needed, and adding the fact that they were cheap enough that, should I damage them in my experimentation, it wouldn't be any big loss.

The dollar store headphones seemed to work better than expected and provided much higher quality sound than I could hope for, but I wanted to make the headset modular, so that should I opt to change the speakers in the future, I wouldn't need to go through an entire assembly process. Suffice it to say, my soldering skills aren't the greatest and attempting to reattach the delicate wires on a headset is less than appealing.

Another aspect I wanted to improve was comfort. With the ear pads made out of bakelite (a pre-war plastic) they could be a bit rough to wear, so I performed a bit of research and found that there were versions that used a leather cover as a padding. So, I attempted to design my own.

STEP 1: Tools and Supplies

Tools;

  • Screwdrivers
  • Dremel with cut-off wheel
  • leather punch set
  • sharp utility knife or roller wheel knife

Supplies;

  • Thin chromium tanned leather
  • foam insulation strips or cut pieces of soft foam
  • wrap around the ear style headphones
  • electrical tape

STEP 2: Disassembly

The first thing you need to do is disassemble your headset. Now, from the three pairs I purchased, there are two different styles. The first is where a set of bolts protrude from the back of each ear piece that act as contacts for the wires, and the second is where the contacts are contained in the housing. I recommend leaving the bolts in place. Not just because they fill the holes, but there is an aesthetic to them in the original design. You need to gut everything else, including the membrane, the two coils and the magnets, which you can keep for future, fun projects.

The wrap around headphones need to be disassembled as well. An important point is to be very careful with the wires at this point. This is a lesson I learned on my first attempt when inadvertently damaged them, but still, it was only $2 wasted. The easiest way to separate them was to insert a slotted screwdriver between the housing and the speaker and give a gentle twist. These cheaper models should pop apart quite easily. I recommend putting a piece of electrical tape over the back of the speaker, where the wires connect to hold them while you work, so that they don't accidentally break during assembly.

STEP 3: Cutting the Slot for Your Wire

As mentioned before, my soldering skills are somewhat lacking, so I decided to take the simpler route, and cut a channel in the base. This would allow me to switch the speakers, in the future, without much effort. First, I had to remove the housing from the wire frame. Easily done, as they are held there on pivots so I just spread the spring housing and they popped right out. I then clamped them in my vise and used my Dremel to cut the channel. On the pair I've displayed here, there was already a hole where the original wires fed through, so I extended the channel to reach that, but on the Brandes model, there is no hole, and so the channel was much smaller. This meant that on the Brandes model, I could tie a simple knot in the wire to stop it from pulling through, but on this pair, I needed to come up with another way to stop that from happening, which I'll get into later.

STEP 4: Installing Your Speakers

Installation was the easiest part of all. For the pair with the existing hole, I simply created a loop in the wire, and set it over one of the screws that protrude inside the housing. This would go a long way to stopping the wire from pulling through. On the Brandes model, I tied a small knot, and because of the narrow channel width, that performed the same task.

As you can see, on the Brandes model, the housing was somewhat bigger than the speaker so I used some foam insulation to fill the free space and hold it in position. It's important to use a porous material as you don't want to limit the airspace. As in larger speakers, headphones require a certain volume of air around them in order to get proper sound. I ended up leaving the foam ear pad on the speaker, but this is completely optional as we will be making our own speaker covers.

Once your speakers are set into the housing, you can screw on the bakelite covers.

STEP 5: Leather Padding

This step is completely optional, but is highly recommended since, without them, the headphones can be pretty uncomfortable. The bakelite covers were 2.5" in diameter, so I cut two disks at 3" and punched a series of holes around them. I then punched a series of holes in the center using one sized punch to create a plus shape, then a smaller punch to add four more holes around.

Finally, I took another piece of scrap leather, and using my wheel cutter, made a lace by cutting around and around in a spiral. You can do this with a utility knife, but you'll find that it's a bit more difficult to keep a consistent thickness. Once your lace is cut, you can feed it through the holes. This can be made easier by using a lacing needle which can be purchased at any Tandy, or other crafting store.

STEP 6: Installing the Pads

Once you've created your ear pads, you can place them over the bakelite covers, and cinch them tight using your lace. Make sure you stretch them well over top and center the sound holes. A good trick is to wet the leather, and stretch them over the bakelite covers. As they dry, they'll take shape and fit snugly, but will still be flexible enough to remove and reinstall without untying. Be sure to do this with the bakelite covers removed if you intend on wetting the leather.

Once your covers are on, you can reinstall your housings into the frame.

STEP 7: Finished

That's it. Enjoy your classic styled headphones updated with some modern sound, and should you opt to upgrade the speakers, the old ones can be easily removed, and the new ones installed in a matter of minutes.

As usual, I hope you enjoyed the instructable and thanks for following.

8 Comments

Well done ! Sweet looking cans

Mikey

I think you will find what you bought were high impedance headphones for use with vintage crystal radio sets, they are not suitable for modern equipment.

that said, you did a nice job with your modification, well done

Ya it's around 2k, but you can put a load matching transformer between to compensate. Just drives your amp a bit harder.

Great looking mod to what would otherwise be no use.

Those are great looking headphones!