spritzer

This one might work: https://eu.mouser.com/ProductDetail/EDAC/305-014-500-202?qs=XeJtXLiO41RmPm5Oq5cTfQ%3D%3D 14 posistions, 1.6mm board thickness and 3.96mm pitch between the pins

This is beyond cool: I have the EV-1's user manual here and it was a fascinating thing

Could very well be but the MLER points specifically to the stators, multi layer electrode rigid, if I remember correctly.

I'm calling BS on it being any different, at least from the pics I've seen so far. The housing clearly is but that has minimal effect on the sound.

Looks to be 350KYen... Funny they are going back to the silver electrodes and they look identical to the first ones I have sitting on my desk. The plastic housing has been changed though

Thanks but I have a local company that does 3D printing for me plus almost all of the PCB companies offer it for next to nothing.

In my forever quest to make electrostatics from cheap dynamic headphones, I just got a pair of these, the Kiwi Ears something or the other: https://www.aliexpress.com/item/1005009234464157.html?pvid=c3232602-d097-4531-93f9-6433fea6c6ac&pdp_ext_f={"ship_from":"CN","sku_id":"12000048952692658"}&scm=1007.25281.473483.0&scm-url=1007.25281.473483.0&scm_id=1007.25281.473483.0&pdp_npi=6%40dis!USD!US %2469.99!US %2459.49!!!69.99!59.49!%402101529317631651718268540ec641!12000048952692658!gdf!IS!134806951!X!1!0!n_tag%3A-29919%3Bd%3A824946d7%3Bm03_new_user%3A-29895&mainPicRatio=1&spm=a2g0o.tm1000037862.2920499520.d0&aecmd=true They seem to be good contenders for this, dual cable entry, earpads which will work nicely for electrostatic duty and they are dirt cheap. The baffle has a row of holes around the driver face but I'd use 4 of them to mount the new drivers and the first PCB will cover up the rest. Some light glue there would help it seal better. This does mean the baffle won't have to be modified at all, just pull out the drivers (which is a pain) and I also took off the foam but it's not that difficult. I've already modified my Superlux/Beyerdynamic drivers to fit them and I'll order some PCB's up tomorrow. The only issue I can see, aside from the usual baffle woes, is the close to zero clearance to fit the mounting screws for the drivers. The earpads are on a bayonet piece and there is no distance between it and the baffle. It is possible to use counter sunk screws and just modify the baffle to fit them flush so that will be my first test. The opening is roughly 46mm and the drivers are 67mm in diameter with a 55mm opening to clear a raised part of the inside of the baffle.

I just checked them and the channel imbalance has drifted a bit but not as bad as they used to get which was completely dead. I'm not sure why they are getting worse though, could be because the coating is too thick. I could barely touch the diaphragm from fear it would rip off the ring completely. I might go in again for a second try or just design new rings to hold the diaphragms. The coating on the DIY sets seems to hold up just fine as I'm currently listening to the Senn HD600e and they are perfectly balanced. The EX-1a is a great and there are still ways around those pesky tariffs for those so inclined... In Stax related news, I just stretched my first ever SR-009 replacement diaphragms tonight. I've already redesigned the spacers a bit but we'll see if these work for a first try. New dust covers and a new way to mount the earpads too which doesn't take an hour to do. These drivers were completely shot but I'll have to wait on some o-rings and screws to work any more on this project.

Years and years of hoarding!!!

I'm using Comfort fabric softener and it works well. Whether it will hold up long term... that's a whole other matter

The drivers are genuine, there is just no way to reuse the stock rings so I had to have my own made. The 009 diaphragm rings make zero sense too as there is no way to solder to them so PCB's here make a lot more sense. Plus more insulation as the stock setup is not ideal. The stators and the case will be stock and I went for slightly thicker rings for the dust covers to add more compression to the drivers. I'm also going to replace all the o-rings with better units. One thing I want to do as well is plug that hole in the center of the stators. I don't understand the reasoning behind it and it might be one of the reason why the 009's sound so bad.

They will have new diaphragms so they will be tonally completely different.

For the cable entry as a prototype but probably milled once I'm happy with the piece. The drivers will be fitted with new diaphragms and dust covers (as they were shot on this set) so that means PCB's for that plus a new way to fix the earpads in place.

Thanks. :) More hopefully on the way soon plus maybe some speakers

Interesting, the 009 cable entry surely can be adapted for that and it makes sense to make just one cable for everything. Edit: I've designed a new cable entry for the 009 project I'm working on but with a fixed cable as I have so many in stock. The stock cable entry is a bit of a joke with that flimsy piece of plastic covering half of it.

One update on my ailing SR-X1, I went in one last time and coated them again and that seems to have done the trick. No imbalance at all and just some mild buzzing from the driver as some debris got in there. I might go in and try to clean it but yeah... that's the good news. Now for the bad one as I'm afraid the X1's are not long for this world. So this was the first time I took the driver fully apart and whoever designed this needs to go and look at how Stax used to be made. I've never seen them do this before but the diaphragm is only attached to one ring, not sandwiched between two of them. So the spacers they use (also the insulation from the stators) are different from one side to the other. The side with the metal ring is very thin indeed, probably 0.2mm or so. I didn't want to snap a picture as the whole thing is so fragile but yeah, the diaphragm is hanging on 2-2.5mm or so of metal spacer and mine was already lifting off the ring as the PEEK seemingly doesn't adhere well to it. I'm sure I didn't cause this and it is very worrying as they have so small a support for the film. I have some SR-X NB diaphragms here and there they used 4mm spacers and glued on both sides for a much smaller diaphragm. That means the films are still just fine after 50 years in service which I doubt will be case for the X1's. I for one don't see an issue with gluing just one side as I do the same on my DIY drivers, but the contact area has to be bigger and mylar behaves differently to PEEK. Right now this set works fine but I'll continue to monitor it and I'd like to know if anybody else has had these issues. I finally got around to watching this and a few interesting bits, they are clearly still making 009 drivers as they were pulled out of a drawer in the soaking oven even through they are long out of production. Odd that they don't swap them out with 009S drivers as they have done with every other model. I did roll my eyes when only 30 X9000 drivers could be tested by one person... sure... why not I found it interesting that they test the drivers like that, as the reflection off the table is surely messing up the test by loading one side of the driver differently. I always thought they would slot them into jigs with microphones on each side as this way makes no sense to me. Btw. I feel their museum severely lacking... I know a few people who have a lot more Stax stuff in their collection than that.

Thanks for that and more projects in the works. While beating my head against the Fusion360 wall I made the parts needed to finally fix the SR-009 drivers. Once you do a deep dive into them, they are so badly designed it just isn't funny. The stators are impressive but the rest is just thrown together. I need to have some prototypes made for the new cable entry to see if it fits with the new mod parts.

I have both in front of me and they have identical cables. The L500Mk2 has the old cable with the white line (the blue was just on the SR-L300) so that should be pure copper. On that note, I've compared all the cables and there is no difference at all to my ears. They all have the same specs that actually matter (capacitance) so they should all perform the same.

What a steal...

Did the color change on the cables from the first release? My first batch sets (X1, two of them and 007S) have identical cables in every way.

While being stuck home, recovering for the past two weeks, I finally got round to doing some more DIY electrostatic headphones. I wanted to try out some different materials, 2um mylar and Comfort fabric softener to do the resistive coating. I must say both worked well and if the Comfort stuff holds up long term, it is a damn good coating that costs pretty much nothing. First off my long standing test drivers in a Superlux HD330 housing... as I had some donor headphones in stock. I made a few of these but this set has the Stax wide PC-OCC cable and Dekoni Fostex hybrid pads. I've made so many of these drivers over the years that they are a good benchmark and they perform flawlessly. Charge up instantly, no charge migration or issue with humidity that I can detect. The drivers are also modular so easy to assemble and test: I didn't even spring for ENIG on these but yeah, super simple design that just slots into the Supelux housing. They are just a bit on the small side for my head and the partially closed housing has issues but it's a fun set to play with. Next up is a set of SR-5's that had severe imbalance. Time for a new set of diaphragms with the thicker spacers I made 10 years ago or. I simply replace the stock diaphragm and this converts them to Pro bias too. Throw on there an old Lambda cable which had a break at the cable entry and it's a great little set of headphones. I love the SR-X Mk3 drivers and they are fun to play with. It is a bit challenging to fit the thicker spacers into the normal bias housings as it can warp the drivers but not a big deal really. Then I put on some leather earpads from my stash and yeah, a great SR-5 Pro... something Stax really should have sold back in the day. While I was making the diapgragms for those SR-5's, I made a couple of more for a spare set of drivers which resulted in this: I'm always on the lookout for cheap open back headphones which can be "easily" turned into electrostatics. This is a Fiio JT1 which was less than 60$ shipped but is not ideal for the conversion as the baffle is not flat due to how the earpads are mounted. Still nothing a circular saw can't fix: I covered the stock holes with tape to seal the baffle and keep the glue out when I fitted the driver: The PU two part adhesive covers all the baffle vents and I put some tape on the earpad attachment points to just keep the glue out of them. Worked just fine and the seal is great No damping at the back and they are open enough. I fitted strain reliefs at the cable entry and plugs to seal off the top vents in the housing as well. This one has the stock earpads and the cable is the standard silicone 6 core stuff floating around with an aluminum cable splitter for the Y split and a prototype plug I was sent a while back. Pretty nice sounding set of headphones that don't cost a lot to make. Granted you need a SR-X Mk3 to donate the drivers and some custom spacers to make it work but I'd want to make something like this with custom drivers. It would be a great DIY project to release, buy this set of headphones, rip out its guts and make your own drivers from these PCB's. The cable is easy to source, so are the cable entry glands and a Stax plug can be 3D printed with basic XLR housings. Finally, a bit of a closure for me with what is probably the final version of the HD580/600/650 electrostatic conversion above. I was always battling baffle leaks on those as it is impossible to shave the stock baffle completely flat. I might try to laser cut a neoprene gasket or something like that but on this one I simply designed a new protection grill and glued that to the baffle. Not ideal but it works nicely. Then new stators and new spacers for the diaphragms and dust covers. The cable is the King Sound KS-H4 unit so it is removable. I just shaved down the socket a bit and glued it into the stock holes. The protection grill which is glued to the baffle. Earpads are the hybrid units Drop used to sell and then sheepskin headpad. New stators with full ENIG plating and purple solder mask because reasons. :) These do sound great if I dare say so myself, very much on par with the HE60 but with a fuller sound. Same spacing at 0.5mm so sensitivity is very close too to stock Senn units. Funny for me as the HD600 was my first ever high end set of headphones, so when I found this set with broken drivers it was an ideal candidate for conversion. Full circle and all that shit...

No. Given the simple physics that the force of an electrostatic field falls with the square of the distance, it quickly vanishes into background noise before even reaching the skin. An amp like this would never be run at full tilt, not into Stax compatible drivers at least. Well past 120dB so permanent hearing damage until they simply burn up. That means the field is even weaker than that in reality. Ideally you'd never want to run the headphones above say 1200-1400Vppss (which is already crazy loud) as depending on the air parameters around you, is could destroy the headphone drivers. Now there are a lot of variables at play here but a rule of thumb says insulation of air is 3kV/mm and we are running at 0.5mm spacing so 1500V. I go a bit lower as humidity is a huge factor here and the new Stax drivers appear to be anything but stable so I'd err on the side of caution with them. I've noticed some very alarming behavior from the X9000 and the 007S so yeah... Stax will never side with you if you have driver damage.

They are just floating around on the Chinese market, there is no one seller doing this AFAIK. The one I bought for myself and the one I gave to Kevin are not from the same seller and used different Stax plugs. Btw. they all come with 5 pin plugs but should never be plugged into Pro bias, 200V max bias for these.

Yes, it should have no problem with that. The only issue might be gain and bias but easy to solve.

I'm slowly working on replacements but nothing that is ready for release yet. The Dekoni pads are well made but I wouldn't pick those as they are too big and I'd never use fenestrated pads due to the air leaks. You'd ideally want 105mm pads with a fairly large opening and there aren't all that many out there off the shelf.