ear defender headphones

might as well start in the most logical place,

the start

this is something I've been needing for work for ages now and while I could buy some, why not make my life more difficult and probably end up spending the same money as I would by buying something off the self?
i'd been planning for a little while how I was going to do it and came up with buying a second set of the ear defenders I use already, some damaged headphones with decent speakers and then all the associated wiring parts I was going to need, which is exactly what I've done.

all the parts are here so I'm hoping to get these put together pretty quick so I can start listening to music at work again without pressing earbuds deeper into my head than feels smart.

depending on how well it goes I'm planning on making a second pair for use at home as well.

more to come soon

update - 2026-02-02

took the first step toward turning these ear defenders into headphones. Drilled the holes in the ear cups ready to accept 3.5mm jack sockets. It's going to be fiddly trying to get them fitted in place as I chose jack sockets where the nut is on the inside. They'll look neat when they're done but there'll probably be a lot of cursing under my breath when it comes time to assemble everything.

update - 2026-03-15 - COMPLETE

After much procrastination, these are now finished. The following happened in fits and starts over about a month when in reality, I could have probably done it in one afternoon.

I fully disassembled the donor Sennheiser headphones I'd bought, keeping the speaker modules and the little breakout board that sent the audio signal between the left and right speakers from the single input jack.
The original plan had been to just keep the speakers themselves but Sennheiser clearly never planned for someone tearing their carefully designed product apart. The speakers are basically permanently sealed inside a plastic housing. After learning this, I took a very deep breath and then started cutting down the speaker modules, removing as much unnecessary material as I could. Photos to the left show the before and after.
I did end up removing a bit more than is shown in the photo, trimming off the corners to make fitting them into the earcups a bit easier.

After that came the first bits of soldering. Attached cables to the jack sockets before feeding them into the earcups. It was at about this point I realised that the plastic of the earcups was too thick for the nut on the inside of the earcup to reach the threaded portion of the jack socket body.
Not to worry, used a stepped drill bit to recess the jacks into the plastic slightly which ended up looking really smart as they ended up flush with the outer surface. Dead pleased with how that came out.
So, back to fitting the jacks. Fed the leads into the earcups, passed the nut over those and then carefully got them fixed in place. Took a bit of fiddling to get them secure but I managed it in the end. After that, I set about making all the connections needed in the right earcup between the 2 jacks, the speaker and the breakout board. More straight forward in the left as it was just a case of wiring the speaker to the jack socket.

They than sat to one side of my desk for a couple of weeks before I decided to tackle making the external cables to link everything together.

Eventually sat down and got on with it and it went pretty smoothly. The only real difficulty was getting the jack plug sleeves over the wire. The wire diameter is the maximum that the plugs will accept so a fair amount of persuasion was required.
With that done, I attached the jack plugs, screwed the jack sleeves down and called it done... not. I did do that but discovered a short in one of the connectors. So everything came apart again so I could correct it.
Now they're done... apart from I'd accidentally trimmed the outer insulation a bit too short on one end of the cable connecting the earcups so I took that apart to fix that and managed to create a new electrical short that wasn't there before... hmmph. So that came apart again, everything was desoldered and then resoldered and is now actually, really done.

For real this time. All that's left is to take them to work and actually start using them.

review

Overall, I'm really pleased with how these have turned out. It would've been nice to not have to redo almost every solder joint at least twice, but it made for good practice. After years of struggling with soldering, I'm finally feeling like I'm getting the hang of it.
The only thing I'm not super happy with is how much space the trimmed down speaker modules take up inside the ear cups. I can feel the plastic of the front face just touching my ear, it's not uncomfortable but it would be more comfortable if I couldn't feel them. I could've spent a bit longer and trimmed off more of the housing, but I didn't want to risk damaging the speaker. Any future pairs of these I put together, I'd probably just buy new speakers from somewhere so they sit further into the earcups and further away from my head. Not a deal breaker, just room for improvement.