[bui501-tech]

Hi Chinsettawong,

Thank you for sending me the new double-sided stators and spacers for the Orpheus clone.
I made extra spacers with 0.8 mm PCB in case the 0.5 mm spacer is unstable with my diagram tension.

I need protect very thin moisture/dust cover film on the front, however sound clarity decreases if place a speaker grill to the front. It looks ugly, but I end up with a fiberglass window screen.

For the headband, I am modifying Sony MDR7506 Head Band that purchased at e-bay.
This is not genuine replacement part from Sony and quality is inferior to original, but it is good for the price.

Wood frames, the first one failed at drilling so I’m making another pair… painting now.
[/QUOTE

Wow! These are really nice! I’ve heard Chinsettawong’s Orpheus clone and I was blown away by them. Your wood housing looks good—should be a great combination.

 

[chinsettawong]

Hi inuponken,

It's great to see that you're moving so fast. I really like your wood frame.

I can't wait to see your finished headphones.

I want to share with you a new trick I learn. As you know, tensioning the diaphragms to be just right is extremely difficult. I now tend to tension them just a bit more than I need. Then I try them on the phones to see if the diaphragms have good stability. I then apply a little hot air to the diaphragms. This makes the tension reduces a little and it makes quite a lot of difference on the the bass.

Wachara C.

 

[chinsettawong]

Hi bui501-tech,

How is your progress on the new headphones? Can't wait too see yours too.

Wachara C.

 

[bui501-tech]

Hi, Chinsettawong,
I'm still working on adjusting the tension to match the larger active area for my larger drivers -- you were right, of course, about the difficulty of getting the diaphragm to stay stable with the larger active area... My first couple of attempts sounded great for about a minute or so, but then as soon as the volume went up, the diaphragm collapsed to one side. I think I'm pretty close to a stable combination. I've only got one test driver working correctly right now, but I should find out in a few days if it's repeatable.

-Vinh

 

[edform]

A little off topic, but definitely to do with DIY Electrostatic Headphones...

I'm in process of building my own headphones and would like some advice on the right amplifier or energizer to buy for testing and use. It's obvious from this thread that a wide range of driver systems are in use by various forum contributors, so I hope that your collected knowledge might point me in the right direction.

My absolute top budget is £1500

1. I could buy a used Stax amplifier, probably an SR-006t; they turn up regularly on auction sites in the £600-£900 range, but it's pretty obvious from things you say here that some third-party amplifiers perform notably better. I have owned a couple of 006ts and found them pretty good with the older 400 series headphones I've had.

2. I could buy a third-party amplifier, but the ones with the reputations cost two or three times my budget.

3. I'm perfectly capable of assembling an amplifier from a kit - not from a schematic - but I have had zero luck in finding any kits that are not considerably more than my budget, even as kits.

4. I could buy a top-notch energizer, I'm intrigued by the iFi Pro iESL model, for example [See https://theaudiophileman.com/iesl/ ]

I'd value a short list of possibilities.

Just to keep this post a little nearer the subject of the thread, Here's a view of where my design is at...

All the metal parts are aluminium. The perforated stators are chemically milled and the stator support spiders waterjet-cut, and all the metal is gold-plated before the stators and their support spiders are bonded together. The insulating rings between the stator spider and the diaphragm carrier rings are also waterjet cut. All the bonds will be made with conductive epoxy, including the diaphragms to their metal support rings. The stators are 0.4mm thick with 1mm holes - I tried to use fine metal mesh but bonding it to the spiders didn't work, even using pre-cut film adhesive. The much more expensive chemically milled plates are the best alternative to maintain non-resonant acoustic transparency to as high a frequency as possible. The inside surfaces of the two stator plates are insulated with a thin layer of electrical varnish.

The narrow windows around the periphery of the stator assemblies leave the diaphragm edges un-driven.

The comparatively high cost of these parts is the main reason I must be economical with the purchase of a driver system.

These panels are intended to be used in a Jecklin Float arrangement - actually a hybrid of the Jecklin Float and the AKG K1000. They are quite large at 125x100mm and are asymmetric, even the stator spiders are off-centre on the stators both vertically and horizontally and are not concentric with any corner radii of the panels..

Ed Form

 

[chinsettawong]

Hi,

I'm sorry to let you know that you will not find a complete kit for the electrostatic amplifier anywhere. There are many great DIY amp designs out there, but, unfortunately, you'll have to do your own homework and buy the parts to build one up by yourself. With your budget, it's possible to build some very good KG amps such as KGST and KGSSHV Carbon.

You've got a very interesting design on your stator. Have you actually built one? What is the width and height of your diaphragm? What is the thickness of your spacers?

Please show us more.

 

[edform]

Hi,

I'm sorry to let you know that you will not find a complete kit for the electrostatic amplifier anywhere. There are many great DIY amp designs out there, but, unfortunately, you'll have to do your own homework and buy the parts to build one up by yourself. With your budget, it's possible to build some very good KG amps such as KGST and KGSSHV Carbon.

I figured the DIY route to an amplifier was probably a non-starter. I do not have sufficient experience at building electronics to do it from a schematic, so I will have to buy something complete. Hopefully others might have suggestions.

You've got a very interesting design on your stator. Have you actually built one? What is the width and height of your diaphragm? What is the thickness of your spacers?

Please show us more.

I've been experimenting with design ideas for a few months now. I began by attempting to bond woven wire mesh to a rectangular aluminium plate stamped with open windows to simulate the stator to spider bond - I used normal epoxy on non-plated metal just to test practicality, but found I could not consistently achieve a flat bond with the wire mesh tight enough across the openings. At that stage I changed the design idea to making the stator as a chemically milled component in thin aluminium sheet and have now ordered some of these parts and some of the spiders, which are being milled from 2mm aluminium on a waterjet mill - there are inner and outer spiders with the perforated stator plates on opposite sides, and tabbed and non-tabbed diaphragm carrier rings to provide the required three terminals.

The diaphragm is 125x100mm with corner radii of 25mm, 40mm, 50mm and 15mm clockwise, beginning top left. It is carried between two 0.4mm aluminium rings of the same shape and 5mm wide, so the moving area of the diaphragm is 115x90mm with 20,35,45 and 10mm corner radii. I've ordered some of these rings as well.

The panel assembly is stacked with insulating rings each side of the diaphragm assembly, and then the stators assemblies, which have the perforated plates inside the spiders. Because the perforated stator plates are the same thickness as the diaphragm carrier rings, the spacing between perforated stator plates and diaphragm is set by the thickness of the insulating rings. I'm having a quantity of these made by click-cutting from 0.1mm Mylar so that I can play with spacing - the panel housing is a pair of plastic mouldings which are screwed together, clamping the panel-stack, so the assembly can be taken apart in a few moments to change spacing. I'll start with 0.5mm each side, but such large diaphragms may need a little more.

The layout of the panel assembly will be clearer in this view...

I should have all the parts in about three weeks from now and will post more then.

Ed Form

 

[Ulfar4]

Hi, I am building estats too, so i wanted to share with you, guys. It took me few months to get to this stage of build. Driver specs are 70mm active area, 0,6mm spacers and 3um mylar foil.

 

[chinsettawong]

Those drivers look really nice Ulfar4.

Please share with us more info. I assume those are made of PCB, right? Do you make them by yourself? What is the amp you are using to drive those driver?

 

[Ulfar4]

Yeah, those are FR-4 drivers and I only drew it in Eagle and jlcpcb.com made it. Thickness is 1mm and it is double sided with vias. The distance from center to center of the holes is 3mm and the holes are 1.5mm.


Amp is DIY too, it is simmilar to Senns HEV-70 amp, John Broskie hybrid amp and Dr. Gillmore helped me with feedback which i have badly designed. It is not very fancy, but I wanted something simple to start with. Maximum output is around 250 Vrms. Now I need to get proper heatsinks to try it more, and make some measurements.

 

[chinsettawong]

Hi Ulfar4,

Thanks for sharing your information. Your stators and spacers are nicely done. I really like them. Looking forward to hearing your impression.

Wachara C.

 

[bui501-tech]

I still haven't built the headphone housing for the electrostatic drivers I've made yet, but I thought it would be fun to cut some acrylic frames for a set of PC/desktop speakers for them. The speaker frame came out looking nice, and they sound really nice with the volume turned all the way up... not really enough bass to be the perfect desktop speakers, but the transparency and soundstage because of the electrostatic drivers sound really good to me. I used some tiny-XLR sockets for the connections at the speaker frames' back -- there seems to be some capacitance issue with the way I've run the wiring inside the case... Take a look at my photos.

 

[chinsettawong]

Wow! Those look super cool!

 

[FastAndClean]

wow people making el stats like it is nothing, crazy thing considering the price of the good el stats those days

 

[inuponken]

Diaphragms 0.8 mm and 0.5 mm.

Ear cups. used t= 0.2 mm (0.5 Oz) lambskin.