[jason41987]

I decided to make this thread for anyone wanting to discuss any ideas, projects, thoughts, questions, etc on making DIY headphones. To share ideas, brainstorm, or collaborate on some ideas. The "open" aspect is it's free for anyone to participate, ask questions, or give advice, or if you want to share ideas and collaborate in an open-source manner.

 

[jason41987]

Currently, I am looking for a functional, strong headband for DIY headphones and there are three ideas I am interested in pursuing further.

My first idea is to go for the AKG style headband, and 3D print a jig I can use to bend a couple wires to a specific shape, cover them with a sheathing, perhaps even just heatshrink, and see how they maintain a shape, and how much spring they have. Metal should naturally have some springiness to it without having to do a full on spring temper of the metal, not sure if the heatshrink covering would help or hinder that though.

The second idea I am considering for a headband is to have a rigid 3D printed headband and utilize a piece of elastic, perhaps a elastic cloth band, some cut surgical tubing, or even large rubber bands over the top of the band into the yoke for the ear cups, to apply tension to the yokes themselves rather than the entire headband.

If none of those ideas work, plan C would be to 3D print a form I can use to simply layer and glue together a composite in the shape I want. With the correct resin, this would easily have enough clamp to work as a headband. Too much clamp perhaps, it will depend on how much material is in the band itself. A couple small strips of it may suffice.

Since I can no longer get a student copy of Autodesk Inventor, I am finding myself having to try out and learn new 3D CAD software so it may take a while before I start making any complex prints. I am currently using SolidEdge, but may pay the $99/year for the student license of Solidworks.

 

[Tofty]

Thanks Jason for starting this thread. Hopefully it can act as a hub for collaborations on a variety of projects.

For an AKG style headband; I can't see the heat shrink sleeving or sheathing affecting the overall springiness of the metal rod used untorwardly. Not over such a long length, with relatively little deflection occurring.
For what metal to use and whether it should be heat treated. Heat treating something that shape, in a consistent manner, at home would be very difficult. 301 stainless spring steel would be a good choice, as it doesn't need heat treating and comes in many different diameters, including 2.5mm, which I feel is about the diameter AKG use. Grade 5 titanium is also an option, but would be harder to form.

I had a go at modelling up a headband similar to the rigid type you described:

It uses a wide piece of elasticated ribbon to provide the clamping force, but any of your suggestions could be used with minor alterations. All parts are printed except for the aluminium standoffs, plastic washers, screws and the elastic.
It's only a rough outline of what's possible currently, although I will make the files available soon, after a couple of small tweaks.

I feel a laminated printed headband is overkill. While a printed single-piece springy headband may not be as robust as other options; from my testing they stand up surprisingly well, so long as it's printed with each layer running the full length of the band that is.
Keeping the amount of flexing to a minimum, by tailoring the fit to one's specific requirements, should allow for a headband that may last decades and even if it doesn't last quite that long, printing a replacement is no great hardship.

I've never used Inventor, but I do use Solidworks and I would recommend it. Also for $99; that sounds like a bargain.

 

[Tofty]

So, for my next big project I want to have a go at making a headphone tuning testbed.
I want to make a frame that allows for quick, tool-less swapping out of various parts, to help identify what specific changes do to the headphone's sound profile and the listening experience.

My plan would be to get hold of some MiniDSP EARS for the more objective measurements and make 2 or 3 pairs of these headphones for side by side direct personal sound comparisons. I'm basically aiming for the audio version of those glasses they use an the opticians; with the clip in lenses.
This is meant as a design that hopefully others will find of use for their own tuning experiments, so I want to try and include as many features as possible and incorporate people's suggestions, as I really don't know what I'm doing.

Firstly, does something like this already exist? What kind of setups have others used in the past?

What things can be adjusted to change the sound profile? (ignoring different drivers and the altering of their venting for the moment)
Open Vs Closed back would be the most obvious variable,
Different side wall and general cavity shape,
Resonators and focusers behind the driver,
Venting around the driver and the specific materials used for any baffling,
The poke guards in front of the driver and any baffling material that may be used here,
Ear pads, thickness, shape, material, etc
Headband clamping force,
Anything else I'm missing?

For the headband design I'll probably use something similar to the renders posted in my above post, just with the elastic adjuster replaced or at least supplemented with a screw adjuster, so the clamping force can be altered manually. The swivel design, which allows the ear cups to turn 90 degrees and lay flat on a surface will be helpful for the replacing of parts.
The arm length adjustment will probably have some form of locking system applied; to keep everything in the same place when the headphones are constantly being put on and taken off.
Forks will become a bit wider; to allow for a larger outer ear cup frame, with room for all the variable components to fit inside of it. The attachment points between the forks and ear cup will either be thumb screws or something super quick release like a Dzus Fastener.
The diver will be retained in a little padded cradle and attached to the outer ear cup frame with minimal spurs. Everything else in front of and behind the driver will slot into the outer frame.

I think that's as far as I've got so far. Rendered images to follow soon-ish.

 

[Tofty]

I still don't have all the parts needed, but I was able to partially assemble my version of the rigid headband: