[chinsettawong]

I've mentioned it many times that the most difficult process in making the electrostatic headphones is to stretch the diaphragm to the just right tension. If it's too loose, you'll have the problem of the diaphragm collapsing to one side. If it's too tight, you won't have good bass. I often have to make many pairs of diaphragms before I feel that I really have the right tension. It's really not easy.

@legopart You should really do more research.

 

[legopart]

I've mentioned it many times that the most difficult process in making the electrostatic headphones is to stretch the diaphragm to the just right tension. If it's too loose, you'll have the problem of the diaphragm collapsing to one side. If it's too tight, you won't have good bass. I often have to make many pairs of diaphragms before I feel that I really have the right tension. It's really not easy.

@legopart You should really do more research.

I done lot of research, but:
- Its hard to remember and apply it all
- Things not always works
- There is no actual roll about the stretching
- Coating amount changing the driver characteristic too (stronger one sided or dual sided) and must of reasons that the membrane stick to the stator is because over-coating

 

[chinsettawong]

I really don’t know how to help you.

Many people here follow my advice and actually successfully built some very nice headphones. I think you need to really believe what people here told you and just follow the advice and just do it. Once you’ve managed to make a successful pair then you’ll know exactly how things work.

Some of your questions are just too strange to answer. For example, “Coating amount changing the driver characteristic too (stronger one sided or dual sided) and must of reasons that the membrane stick to the stator is because over-coating”. What are you trying to say? Do you not believe that coating on one side works? There is no relationship between coating and the diaphragm collapsing to one side. Please try to understand it.

 

[legopart]

I really don’t know how to help you.

Many people here follow my advice and actually successfully built some very nice headphones. I think you need to really believe what people here told you and just follow the advice and just do it. Once you’ve managed to make a successful pair then you’ll know exactly how things work.

Some of your questions are just too strange to answer. For example, “Coating amount changing the driver characteristic too (stronger one sided or dual sided) and must of reasons that the membrane stick to the stator is because over-coating”. What are you trying to say? Do you not believe that coating on one side works? There is no relationship between coating and the diaphragm collapsing to one side. Please try to understand it.

Ok, my mistake!
on ESL some using high resistors (20M OHM or more) for the bias to try overcome arcing problems

I promise you that I read on the past lots of pages here,
I will read it all again.

thanks for help.

 

[qu1en]

Ok, my mistake!
on ESL some using high resistors (20kOHM or more) for the bias to try overcome arcing problems

I promise you that I read on the past lots of pages here,
I will read it all again.

thanks for help.

I think you should focus on one thing at a time. Get a known working energizer (like a STAX) and just focus on the headphones only. This way if you have an issue, you will know it is the headphones and not the energizer. Otherwise you will just drive yourself mad.
Once you get your headphones working, then maybe you can design your own energizer. I use a 20 Meg in series with my bias, but even if it was not there, it will not arc.
Please look at the photos of OP and others have posted on here on the stators and diaphragms. If it doesn't look almost exactly like their photos (tight clean diaphragm, flat and clean stators, no bends in the spacers, no wrinkles in the diaphragm whatsoever) it will work.
Some of the photos you posted looked quite bad. The black material you used for your stators, I couldn't make sense of what it was. The stators had like three or four holes in it and the holes looked like they had burrs. Not sure how you expect to get any airflow or sound through them.
They looked nothing like the stators and rings that everyone else has posted. I think the tension of the diaphragm is the least of your problems. You really need to get the stators and rings very clean and precise. Then tension the diaphragm so that there are no wrinkles at all. Finally, you should try and copy these designs and get it working before trying new ideas.

 

[legopart]

Acctually I talked about the attempt to restore the Stax Lambda headphones.

Finish to restore Sr-202, the old signature back even with 2micron membrane, and I hate it!!!
glue it little bent, not 1:1 on the stators holes
I just so clumsy and unprofessional.

Life less sound! bad and dry ear-pads.
some said it because the low quality cable that having high capacitance on purpose, to make the sound less warm.
(some said that this is the same drivers that installed in sr404 and sr-sigma-404 )
this is the most low level of Stax I ever heard!

I have the Stax Lambda Pro, that having life full sound.
This is my reference headphones (and untouchable for any mods)

I can't do nothing to fix the Sr-202.
Still preper to fix my first electrostatic headphones that broken after I tried to clean them.
The Sr-Lambda Normal.
I carved before gluing it together 0.5mm hole for the stators.
Don't know how it capable and safe (1mm or less air distance between the stator and the bias), but after I will install/glue the membrane and hop to restore,
I still not have any specific Pro cable for them and the price for new one is too high.
can dissasamble the Sr-202 cable for any experiment.

and less about the fail version of my headphones...
I actually not having any CNC so I cant really create things on level that the members here can.
thanks for the explaining, I found by myself too lots of issues and I will try to avoid them next time.

My plan is ... to wait until tomorrow when its dry and then throw it...
it's looks bad and it definitely will not work.
I think that with this try I will quit from ESH-DIY, sorry.

first attempt always fail, and it really looking ridiculously.

Not like to wait.
I cut it from the film, check the continuity and then solder it.
I made it too flexible + overstretch it.
done it too clumsy.
2-4 hours of work+ 16 hours of waiting

it sound too low and too scretchie
I gonna throw it and just learn from this trying.
it gonna be hard to make ESH without working tools and knowledge.

got to find some easier DIY, or get lots of more knowledge and ability

 

[qu1en]

Acctually I talked about the attempt to restore the Stax Lambda headphones.




and less about the fail version of my headphones...
I actually not having any CNC so I cant really create things on level that the members here can.
thanks for the explaining, I found by myself too lots of issues and I will try to avoid them next time.

Fixing a Stax headphone is probably difficult. I won't even attempt it because i'm sure I'll just ruin it.
If you don't have a CNC machine with the correct material and thickness, or use FR4 and design PCBs to the proper thickness then you really don't have a chance.
If you try and manually cut and drill holes it won't work. The pics you provide shows that nothing is completely flat.
You're talking about 0.5mm which is so small that even a poorly drilled hole, or flexed stator could exceed that thickness.
This should be obvious honestly, you're dealing with very tight tolerances so everything has to be flat and clean.

 

[legopart]

Fixing a Stax headphone is probably difficult. I won't even attempt it because i'm sure I'll just ruin it.
If you don't have a CNC machine with the correct material and thickness, or use FR4 and design PCBs to the proper thickness then you really don't have a chance.
If you try and manually cut and drill holes it won't work. The pics you provide shows that nothing is completely flat.
You're talking about 0.5mm which is so small that even a poorly drilled hole, or flexed stator could exceed that thickness.
This should be obvious honestly, you're dealing with very tight tolerances so everything has to be flat and clean.

Yes, as you said,
I having only ordered material with 0.5mm thickness.
not having CNC, only drill and some Round cutters, I can cut only round shapes.
I have some dremel addition that turns it into router

Still no skills or accuracy, nothings cant promise that even after gluing I will not glue the membrane to the stator


although I having lots of ideas how to overcome the the absence of CNC and even the skills to use it, and still to create some ESH .
if it will success (or even if not), I will share it here.

 

[qu1en]

Yes, as you said,
I having only ordered material with 0.5mm thickness.
not having CNC, only drill and some Round cutters, I can cut only round shapes.
I have some dremel addition that turns it into router

Still no skills or accuracy, nothings cant promise that even after gluing I will not glue the membrane to the stator


although I having lots of ideas how to overcome the the absence of CNC and even the skills to use it, and still to create some ESH .
if it will success (or even if not), I will share it here.

"I having only ordered material with 0.5mm thickness"
This will work for the spacers (ring) but will not work for the stators. 0.5mm is far too thin for stators because it will bend easily. I use 1.6mm thickness for the stators with copper on one side.

 

[legopart]

Probably dust between the stators and membrane.
You just wrote you left the dust shield off, The high voltages attract dust....
Switch off and unplug headphones, then gently blow into the stators to hopefully remove any dust.
It will keep happening if you don’t put the dust shields back after a thorough clean.

Great ideas.
I really applied it and it fixed the problems of the white noise,
unfortunately I find some unglued part of the stator on the Stax Lambda, at this point tried the cement glue to overcome this.

last attempt to fix my Sr-202 ends with this graph after finish assemble them (using high tension membrane.)

Still not good enough for me, not enough bass.
plan to reassemble them.

At this point I plan to finished to assemble the Stax Lambda Normal, that I extend the distance between the membrane and the stator to 0.5 (so now it Pro biased.).
applied the membrane with low tension.
After fully assembly, I will share the results and the fraph

Spoiler: -

*Update, one side still got lots of distortion

The only working side sound good, but the measurements not the best
*the second I decided not to test

Spoiler: only right

ok, made the second driver function, somehow

*The results not so good, and even the fact that I tight the membrane together it still looks not the same.

"I having only ordered material with 0.5mm thickness"
This will work for the spacers (ring) but will not work for the stators. 0.5mm is far too thin for stators because it will bend easily. I use 1.6mm thickness for the stators with copper on one side.

Yes... its one of my mistakes.
thanks.

 

[lkos98]

Well at least it's a progress. By the way it doesn't look too bad, are you sure the phones were sealed good to the measuring device (whatever it is)? The peak in 100 - 120 HZ looks a lot like a free air resonance.
CNC (or 3D printer) is very, very useful (actually I made my CNC, just because I wanted to make ES headphones), but still you can make them with the dremel, sanding the burrs (I also do a lot of sanding after CNC drill and cut), filing the edges, etc., so you get flat stators. Drilling 2-3000 holes by hand (estimating at least 500 per stator) is not very pleasant (my CNC makes 4 stators for about 3 hours and I barely stand waiting for it to finish).
The 0.5mm PCB is a problem, but there is solution there as well - glue with epoxy 2 or 3 of the PCBs (before drilling ) pressing them very hard between flat surface MDF or similar, and here you are - 1-1.5 mm with pretty good stiffness. There's also another option - create a gerber file for the stators and sent it to a PCB manufacturer (won't give any name, not to sound as advertisement) and they will do the job for you. Not sure you can do the same for the spacers - don't think they work with 0.5 mm PCB.
The possibilities are countless and that's what makes this so much fun.
In any case - do a lot of reading, and searching and ..... reading. And as said - focus on one thing - don't jump from one cloud to another. Just go on and at some point it will bring you a lot of satisfaction.

 

[Tachikoma]

*I know this is a bit off-topic from the current discussion, but I'm not sure where else I should put this.

I've been trying to recoat my SR007 over the past few days, and I have finally worked out a procedure that seems to produce decent results.
1. Mix floor cleaner in a 1:4 ratio with water (1 part floor cleaner, 4 parts water). Diluting the floor cleaner increases the resistivity of the coating, and thus, the loudness of the driver. I _think_ its a little more stable this way too.
2. Clean the membranes prior to coating, then dry with air (I use a rubber dust blower... which is a rather laborious process).
3. Use a soft sponge to apply the coating - I use liberal amounts of coating here, and only on one side.
4. Dry with air, again.
5. Buff the coating until its clear-ish (to "homogenize" the coating across the membrane and remove excess coating) - I used a soft cloth made of synthetic fiber (read: sports jersey) to do this.

Note: Maybe don't bother buffing the membrane if its a vintage model, the membrane is a little too easy to damage.

The coating seems to stabilize after ~24 hours. The loudness/balance of the drivers may change slightly over this period of time.

This procedure is basically identical to Chinsettawong's procedure, which he posted somewhere in this thread. The only difference is that the floor cleaner is diluted rather than concentrated.

Coatings I've tried before this: Staticide 6300, various screen cleaners, soap, and undiluted floor cleaner. My experience with (undiluted) Staticide 6300 is rather negative, because the balance changed randomly after a while, but maybe its because I didn't buff the membrane after applying the coating. Its also damn near impossible to remove the Staticide 6300 layer once it has settled.

 

[chinsettawong]

It’s glad to know that other floor cleaners also work. I’m not so sure about your comment about having higher resistivity and the loudness is higher though. Anyway, thanks for sharing.

 

[Hi-Fi-Apricity]

What's a good CNC people here recommend for working on the stators and wooden enclosures? Particularly for someone that's new to CNC machining. Thankyou

 

[Tachikoma]

It’s glad to know that other floor cleaners also work. I’m not so sure about your comment about having higher resistivity and the loudness is higher though. Anyway, thanks for sharing.

I started by recoating only one channel (the other channel still had the coating you did for me ), which allowed me to compare the loudness of each coating to a reference. Diluting the coating to increase resistivity is something that has been discussed a fair bit on diyaudio, so I figured that it was worth a try.