Hi all! I’m Dan, and I’ve been working on a headphone I plan on bringing to the market quite soon (very specific, I know). This started as a 3D-printed DIY project that just sounded so danged good (in my totally unbiased opinion) that I’m now working towards selling them.
The brand is Lithium Headphones, thanks to my dad - he’s a retired science teacher, and my original design looked like an atom with two electrons, thus lithium.
I want to note that I am in no way, shape or form an engineer. I’m an audiophile and a tinkerer with way too much time on my hands (not really) who stumbled into a damping system that’s pretty freaking solid.
Here’s my final prototype:
Along the way there’s been a lot of trial and error. Probably more error than trial. For instance, this was the first DIY headphones I made when I got my 3D printer:
Best thing you can say about them is they worked and sounded like DIY headphones. But I was hooked.
Here’s a bunch of my earlier prototypes and a little Totoro I printed for my kid:
Development took place mostly in Tinkercad in the beginning. I didn’t have any experience with CAD design, so it was a great platform to cut my teeth on. As the sound improved and I got more serious, I started working in Blender, and then Fusion360, which is where all my designs now live. Learning curve was fun - if you’d asked me a year ago if I would ever know how to use a professional CAD program to create something, I’d have laughed at you. But now I’m good enough to be dangerous.
The real breakthrough came with what I’m calling the Lithium Damping System. Taking some inspiration from John Masseria over on another forum who mods headphones by adding layers of stiff fiberglass mesh over them, I designed a stacked damping system to go between the drivers and the pads. These blow out soundstage really nicely. Then I made a smaller, more delicate and detailed version for behind the drivers, which has a noticeable effect.
The result is a very resolving, really well-balanced sound with what I consider to be excellent soundstage and separation (although the market will tell me if that’s just my own self-importance speaking).
Another element of the design is passive radiators. My initial thought was to try and recreate the venerable AKG K240 Sextett design - the driver surrounded by six passive radiators. The big monstrosity I first made was that. It was all-bass, all the time - thanks to my sourcing and placing of six 30mm passive radiators. To be frank, it sounded like bassy butt.
I cut the baffle design down to 4 holes for radiators around the driver, and I tune each design based on desired bass response. For a bass blast (but still fun and listenable), I’ll pop 28mm radiators into all 4 holes. For a slight elevation of bass, just 2. Otherwise, I use felt to cover the holes so there’s no reverberation coming through; the felt over the holes gives just a little added sound absorption to go with the Lithium Damping System setup.
Right now, I’m making all of these myself in my house with a collection of FDM and resin 3d printers:
The initial batch I’m going to sell will be 40 headphone pairs, all made by hand with my own equipment. I hope to be able to get some traction and fund a more scalable injection molding process.
Here’s the breakdown:
40 headphones
- 20 with 300 ohm beryllium-coated drivers
- 20 with 600 ohm beryllium-coated drivers (still on that Sextett kick)
Hart Audio dual-3.5mm cables, terminating in 1/4"
1 set of pads (TBD)
A carrying case (finding the right one still, between Monoprice and Pelican at the moment)
Finally, for the numbers-minded, here’s a FR graph I took with a MiniDSP EARS. Take it for what it is; the EARS I know is very low-caliber for FR graphing, but it’s what I have available to me. This is with my prototype 540 ohm beryllium drivers, driven by a Bottlehead Crack w/Speedball.
Pricing is still a little up in the air; much will depend on what my final cost is, but the first 40 will be at a lower price since they’ll be 3D printed at home. Looking forward to getting this out there, it’s been a fun adventure already and I’m really hopeful people think they sound good.
Oh, here’s my home listening setup I’ve been using these with:
Not pictured is my Burson Timekeeper 3i which is serving as my DAC. These absolutely love tubes (unsurprisingly given the impedance) but sound really, really good on the TK as well.
I’m open to questions, criticisms, hurled insults and offers of beer. Want to be as open-book as I can about the whole development process; I’ve learned a lot about the hobby I love by throwing myself in there and making a thing.
The website is under construction but we’ll be at lithiumheadphones.com. And by “we” I mean “I,” since it’s just me. Timeline-wise, I have all my drivers and have started producing the printed parts. I’m waiting on pads and cables. Big shout-out to Hart for being really responsive and supportive. I will of course offer a return policy and a warranty; writing that up at the moment.
