[kakaworu]

Not long ago I put some DIY parts in cart by the way when I was buying ChiFi earphones, including a pair of 50mm beryllium coated drivers.

Since I've built a 3d printed headphone conversion for KSC75 before---although it was a failure.
I want to do it again to see if the 3D printing headphone works. I've referenced many pictures of MDR-R10 on the Internet and made a tribute to it.
I tried my best to replicate the cup shape of R10. it is only designed with reference to the picture. Of course the measurement is impossible to be accurate.
The baffle was oval because I happen to have some pads for MSR7.
I don’t have any experience in acoustic design. So I can only design with reference to my own headphones and some headphone photos.
----Too bad I have not read Frank2908's article before i did this.

The cup is closed-back design though it has two parts I glue them together to prevent any air leakage.

The vents are all on the front side, around the drivers.

The driver compartment is tilted by 10 degrees covered with fibonacci grill.

I did not use blu-tack or dynamat in the cup. I stuffed urethane foam in it instead. And I filtered the vent with micropore tape.

By the way, the connector is MMCX since I only have MMCX for now.

It weights 203g without cable and pads. 280g with these sheepskin pads.

These beryllium coated drivers are very similar to those on the HamonicDyne headphones.
These were cheap so i guess they might be the same ones on the Helios(?
Sound-wise. With my design and damping methods. It sound V shaped quite obviously. Bass is better than i imagined.
Mids not bad. Treble is a bit hot. Lots of detail but sometimes too harsh in higher volume. Less harshness after i squeeze more foam in the cups but still there.
Soundstage is not good.
I'm thinking about how to reduce harshness farther. And I am wondering if i can improve the soundstage by drilling a few small holes in the cups.
But i'm afraid that doing so will increase the harshness.

Or maybe the driver just doesn't fit a closed-back design. I don't know.
Guess there are so much tweaks i can experiment to reach the sweet spot.
Hope I can make this a platform for me to try those mysterious Chifi driver units.

Any ideas or suggestions are much welcome.

 

[NA Blur]

Awesome work.

Ideas:
1.) Thicker pads. Make then at least 2cm thick and from good memory foam
2.) Tilt the pads a 5-10 degrees so the back of the pads are thicker. This couples the drivers to the ear better for more bass impact.
3.) Use pleather pad material as it holds up
4.) Make the pads circular instead of oval or oblong. Think something like the HE-400 pads
5.) Add 1.5cm of thick padding to the head-side of the headband for long-term comfort.
6.) Most importantly, keep up the great work!

 

[kakaworu]

Awesome work.

Ideas:
1.) Thicker pads. Make then at least 2cm thick and from good memory foam
2.) Tilt the pads a 5-10 degrees so the back of the pads are thicker. This couples the drivers to the ear better for more bass impact.
3.) Use pleather pad material as it holds up
4.) Make the pads circular instead of oval or oblong. Think something like the HE-400 pads
5.) Add 1.5cm of thick padding to the head-side of the headband for long-term comfort.
6.) Most importantly, keep up the great work!

Thanks for your advice friend. I happen to have 2 different types of 110mm pads.
So I printed a pair of 110mm baffles and tried them briefly.


The angled pads are quite thick. They are like 40mm in the back and 25mm in the front.
The distance between the ear and the driver is greatly increased, making some irritating resonance and pushing the vocals away.


These perforated pads are 25mm in thickness. They took all the bass away. Makes it sounding thin and even more harsh.
I guess they are meant for bassier drivers?


So i went back to these oblong pads and did some venting test.
After drilling these holes, it sounds much better. The soundstage increased slightly.
The harshness was perceptibly reduced. I need to upgrade my measurement rig to conform that.

Is it still a closed-back headphone with these tiny holes?

 

[NA Blur]

You will have to look into a basic frequency response measuring system. I think you can find something relatively cheap and use your phone if need be.

 

[furyossa]

Thanks for your advice friend. I happen to have 2 different types of 110mm pads.
So I printed a pair of 110mm baffles and tried them briefly.


The angled pads are quite thick. They are like 40mm in the back and 25mm in the front.
The distance between the ear and the driver is greatly increased, making some irritating resonance and pushing the vocals away.


These perforated pads are 25mm in thickness. They took all the bass away. Makes it sounding thin and even more harsh.
I guess they are meant for bassier drivers?


So i went back to these oblong pads and did some venting test.
After drilling these holes, it sounds much better. The soundstage increased slightly.
The harshness was perceptibly reduced. I need to upgrade my measurement rig to conform that.

Is it still a closed-back headphone with these tiny holes?

Congrats man. You did a really amazing job here.
Of course, wood be a much better option (like Sony MDR-R10) but I appreciate more of your DIY handiwork.
The design is really beautiful, you chose a very powerful color combination (warm and vibrant). Just keep up good work.

 

[ejacobsen]

Extraordinary work! Thank you for sharing.

 

[furyossa]

Extraordinary work! Thank you for sharing.

I hope to see another interesting DIY project soon

 

[kakaworu]

At the request of a friend from a 3D print filament manufacturer, I started working on this project again since last month.
We're going to demonstrate some 3D printing filaments with these headphones.
So I did some refinement to the design, and try to tune the sound better.

With the same 50mm bery driver, I reduced the vent size in the baffle part.
And I made the cushions magnetic-attached. So I can try different cushion materials or sizes rapidly.

On top of that I changed the cup design to semi-open. And it sounds MUCH much better.
Well they sound REALLY GOOD with some drivers I've bought from China.

Besides, I also built a "drop-in" version for KOSS KSC75.

No need to damage the KSC75 itself. No desoldering work. Just remove the clips and put them into the printed parts.

But this one change the KSC75s' sound significantly. It sounds more boomy, too boomy for me, actually.
And it narrowed the soundstage slightly.
Still, a fun project. And putting them out for an exhibit is going to look cool especially when you realize they are almost fully 3D printed.

There's also a open-back version. I'll update later when I finish photo shooting of them.

 

[kachoo]

This is a really cool thread, I think the KSC75 drivers were the right choice for this type of project, makes it more accessible as well.

What was the reason for choosing the R10 style housing? I know it's a renowned headphone, but there's so much going on behind it that mimicking the shape likely fails to recreate the purpose the original design had. At the very least, It's a unique style I suppose. Thinking of printing something up very similar to this. Congrats on the work so far.