Ribbon or planar headphones

[Neil Davis]

Originally posted by setmenu
Nice to see another foray into ribbon headphones.
Here is a pic of a transducer i made a while back, it uses a coil etched on a flexi circuit material.
The pic shown has more turns than the final version.
I have made several pairs of phones using the design , and they sound rather nice.
Mark

It looks like you could modify the design a bit to use the diaphragm from a HiVi RT1 or a similar small planar. The thinner traces and lighter weight backing would increase the efficiency, and there would be a much smaller magnet gap that would also increase efficiency. The down side of using the RT1 diaphragm is that the surface would be more rectangular--something like 2" by 3/4". However, you could just use part of the diaphragm and fold over the unused section. You could also stack two of them side-by-side.

Of course, this raises the question whether the smallest BG tweeter could be used as a headphone element. Might be worth an experiment...

[Neil Davis]

Originally posted by Spasticteapot
Ooh, nice - 24 microns thick with copper! Aluminum would be preferable due to reduced mass, but it's hard to argue with the convenience.

A commonly quoted thickness for a "typical" planar diaphragm is around 12 microns for the aluminum traces and 12 or more microns for the backing. Or, about .5mil for each. It turns out that kitchen foil is about this thickness. You can buy .4mil polyethylene at Lowes, and with a layer of spray-on or brush-on adhesive you can make a diaphragm that is very cheap. That's what I did many years ago for those DIY Heils that were written up in Audio Amateur.

But I wouldn't bother--because I think you can use the diaphragm from an RT1 or something similar and get better results.

[Ed Holland]

Having just completely rebuilt my Magneplan SMGa's, I suppose that construction technique could apply to headphones rather easily. It takes some preparation to lay out the 2 foot runs on the speaker by hand....

I have lots of Al wire remaining from the repair kits, although one might use super fine stuff from any source if you are willing to experiment. Contact adhesive is cheap, and one doesn't need many magnets. There's also the chance to experiment with diaphragm material, resonance damping etc...

Just a thought,

Ed

[owen]

How about using some of the Apex Jr tweeters - if you gathered 4, you could build 1 pair of headphones - they have a spiral wound transducer, and a single perforated magnet - you need to switch the back planar magnet out for a perforated one, but hey thats a minor technical challenge

Just a thought



Owen

[tmblack]

Anyone tried making headphones like little Magnaplaners yet?

[wualta]

From scratch? No, but we have used dipole versions of the SFI tweeters sold by Apex Jr., driven full range, to make headphones.

Doing a proper printed-circuit diaphragm would not be easy or cheap, but with a pen/marker loaded with conductive ink/paint you could draw a serpentine voice coil on some bo-PET (Mylar), hang it ribbon style (free to swing in the middle) and sandwich it between two perforated magnets (upgraded rubber fridge magnets, like the ones Wharfedale used 40 years ago) as a proof-of-concept. The efficiency would be terrible, but so what?

[Pano]

Thread moved to Headphone section

[jcx]

as a class these are called orthodynamic headphones - at least the ones with plastic membranes and serpentine trace - there are some recent "high end" commercial products HifiMan HE-5/6, Audeze LCD-2

heavy magnet structures, extremely low efficiency - not for everyone

[Cyan]

I cannot wait anymore for the new transmission audio headphones. I don´t like the planar lcd-2. They don´t have highs as good as my speakers who have a true ribbon fountek 3.0. The owner of the company said that they will cost less than electrostatic headphones, but I wonder what electrostatic headphones he´s referring to...

[tmblack]

Try the Fostex T20RP headphones very similar to vintage orthodynamics.
The sound is not like electrostatics, more like little Magnaplanar speakers!