[Torac]

Hi,

Been working on this project for a few months now and thought it would be nice to share. I have been working on making my own self designed and constructed Planar drivers. My intent is to eventually try and sell them for diyiers or anyone who wants to get their hands on a pair to experiment with tuning or transplanting them into existing headphones, whatever they like.

I have made many working prototypes at this point, the first using a 25 micron copper kapton substrate and more recently 13 micron aluminium mylar, all with an active area of 48mmx50mm and a diaphragm size of roughly 70mmx50mm. I have gone with a dual sided isondynamic style design using 3mm n52 neodymium custom bar magnets on each side.

I am currently waiting on a new diaphragm material I have ordered, but currently I think it sounds pretty nice to me.

Here are some pictures of my current driver and a graph I measured using rew and a umik-1 mic:

This driver currently using version 2 of my trace designs which measures as 21 ohms and has 7 'turns' but when I get the new material I hope to use version 3 which in previous attempts measured as 31 ohms and has 14 'turns'.

Here is a picture of that:

I will update this post with progress as I go along.

 

[Ulfar4]

Very nice work.
Is there any shop where you can directly buy the diaphragm material?

 

[Torac]

Very nice work.
Is there any shop where you can directly buy the diaphragm material?

Unfortunately not as I have been making most of the material myself, I have an 8.5kg roll of custom material arriving soon as that was the minimum order quantity I was able to get made...that plus another 8.5kg roll I'm having stored as I really didn't need that much. I could potentially put some on another roll if you want a small amount, what would you want it for if you don't mind me asking?

If you want it for making electrostatic drivers I can link where I buy my plain mylar as they supply down to 0.5 micron stuff.

 

[Ulfar4]

That is what i was affraid.
Sure you can ask. I am tempted to try build planar magnetic headphones. But I did not find suitable material for diaphragm that I can bought.

 

[Torac]

That is what i was affraid.
Sure you can ask. I am tempted to try build planar magnetic headphones. But I did not find suitable material for diaphragm that I can bought.

If you just want some material to start with I would recommend to try this stuff: http://simaintl.com/store/aluminum_mylar_PET_tape.html

 

[Torac]

Good and bad news...but mostly good

The custom material arrived!

It is better in a lot of ways but is more difficult to work with, for instance, V3 of my traces is near impossible to produce consistently, the good news is that V2 now measures as 30.2 ohms since the aluminium is a lot thinner which also reduces the overall diaphragm weight and since the material is laminated instead of being glued it ensures I don't get any delamination which would cause rattling. Very happy with the sound of the drivers and have ordered a couple of sets of my magnet baffles to be made out of laser-sintered nylon so I can make a couple of productions pairs which I will make a website for soon. If all goes well and I see that there is interest in this kind of product I will be able to make more! Cannot wait for others to hear my final design

 

[Torac]

Small update. I have found a better method for etching which produces better more reliable results.
Here is a V2 I etched today:

 

[Ulfar4]

Something is probably wrong with the link of you picture.

 

[Torac]

Something is probably wrong with the link of you picture.

Fixed it, thanks for pointing that out.

 

[Tjj226 Angel]

Mind sharing the etching process?

Im gearing up to use a laser printer to print the pattern on some aluminized mylar. Its kind of hard to do since you have to first put the mylar on some paper so that you can feed it through the printer.

 

[Torac]

Mind sharing the etching process?

Im gearing up to use a laser printer to print the pattern on some aluminized mylar. Its kind of hard to do since you have to first put the mylar on some paper so that you can feed it through the printer.

I'm using a solid ink printer for my method. Tried using a laser printer but never managed to get a good toner transfer. Aluminised mylar is also unadvisable as aluminium thinner than 0.5 micron has a really high impedance unless of course your material uses thicker aluminium then go ahead

 

[Tjj226 Angel]

I'm using a solid ink printer for my method. Tried using a laser printer but never managed to get a good toner transfer. Aluminised mylar is also unadvisable as aluminium thinner than 0.5 micron has a really high impedance unless of course your material uses thicker aluminium then go ahead

"supposedly" my material has a 1 micron thick layer of mylar and 1 micron of aluminum.

If that turns out to be false, then I am screwed. I haven't found a ton of viable materials here in the US, and the materials I do find are restricted to industrial use where you have to buy in bulk.

I do have a ton of 2um mylar for electrostatic projects, but I have never found a good method of bonding aluminum foil to the mylar.

 

[Torac]

"supposedly" my material has a 1 micron thick layer of mylar and 1 micron of aluminum.

If that turns out to be false, then I am screwed. I haven't found a ton of viable materials here in the US, and the materials I do find are restricted to industrial use where you have to buy in bulk.

I do have a ton of 2um mylar for electrostatic projects, but I have never found a good method of bonding aluminum foil to the mylar.

I don't suppose you could link me to this 1 micron mylar & 1 micron Aluminium, if it is true that sounds perfect. I too haven't found a good way of bonding aluminium to mylar, best way I have found is to use scotch weld 77 but the main issue with that is that it is dissolved by paint thinner which is needed to remove the ink after etching.

Was trying to attach 0.5 mylar to 0.5 aluminium at one point...didn't really like being printed on though.

 

[Tjj226 Angel]

I don't suppose you could link me to this 1 micron mylar & 1 micron Aluminium, if it is true that sounds perfect. I too haven't found a good way of bonding aluminium to mylar, best way I have found is to use scotch weld 77 but the main issue with that is that it is dissolved by paint thinner which is needed to remove the ink after etching.

Was trying to attach 0.5 mylar to 0.5 aluminium at one point...didn't really like being printed on though.

https://www.homefly.com/products.asp?id=31

Im very skeptical though. They don't have an specs on the material, but I have heard from a few people that the stuff "works" and that it should be half mylar and half aluminum.

What we really need is aluminum and mylar laminate.

 

[Torac]

https://www.homefly.com/products.asp?id=31

Im very skeptical though. They don't have an specs on the material, but I have heard from a few people that the stuff "works" and that it should be half mylar and half aluminum.

What we really need is aluminum and mylar laminate.

Interesting, I did see this a while back but figured that it was just standard aluminised mylar with too thin aluminum, do let me know if it works for you though. If only single sided laminating machines were cheaper then we could just make some