spritzer

The drivers are the same except new diaphragms and naturally new diaphragm holders for both dust covers and the main films. The material, tension, treatment and even the direction of the tension is all crucial to how the headphones sound. Still with the stock housings and stators, there is only so much that can be done. Now sure what green PCB you are referring to though? There is nothing like that in the stock headphones.

Now it shouldn't come as a massive shock to anybody but I'm not much of a SR-009 fan. From day 1 they always sounded messed up to me and the BK and S didn't really make it any better, even a bit worse with the 009S. To this day I have only one 009BK (as it is a limited edition) in my collection and one regular 009 that showed up here randomly and was a stark improvement over all the other sets I've owned. No idea why those sound different but better not mess with them. Now the plan was always to do something with the 009's to improve them but there was always something better to do. Well with surgery pending a couple of months ago, I finally had time to do something not too taxing. First off I needed a donor set and here is where that came in: I got these three years ago and they just sat there in a box. Too many parts missing with no spares available, three out of the four dust covers were trashed and I took off the arc to rescue another 009... so a pile of parts with fucked up drivers. The plan forward was clear though, the drivers needed new dust covers, new diaphragms, a way to mount the cable and finally some way to attach the earpads which wasn't 009 levels of stupid. Now none of those parts could be reused or they simply weren't there so time to do some designing. I still suck at 3D design but practice makes perfect... or it should in theory. Now first off, dust covers and diaphragm holders. These are easy to do as PCB's but materials, thickness, films used etc. are all large variables. Here are my first drivers, actually using the third batch of diaphragms as I slightly tweaked the dimensions once I started test fitting: Those familiar with the stock drivers might spot the bias connection is very different. I had to spend a lot of time cleaning the stock drivers, as they had been open for who knows how long, but this first test was successful. Fully balanced drivers and no noises from them at all so they are as clean as I can get them. The dust covers are 2um mylar-C, just lightly stretched (hence the slight lines visible) and the main diaphragms are also fairly loosely stretched 2um mylar-C, then heat treated and given a coat of fabric softener. The drivers are easy to align but one major part of this project is to find all the correct o-rings used to assemble these and in the right grade. When I had waited a month for a large shipment just for the one size I needed to not show, I even bought some stupid expensive examples locally. That got me here: All new screws used to get the drivers into the housings. You can see how beat up the aluminum housings are but hey, fine for a project like this. Now there was the next difficult bit, the cable entry: On the stock set it is a plastic guide which sits in those holes, the cable fits in that and the whole assemble is screwed down. Now the stock cable I had was not perfect so instead of making my own version of that... I just used a standard Lambda cable. A L500 was going to die for this set anyway (as I needed the arc) so why not use that cable. Here is my solution for that: This is 3D resin printed and is the second revision. First was just to check for hole size, alignment and if it was fouling on anything but it was way too shallow. This version still had to be sanded a tiny bit but it fits nicely. I did make a 3rd and 4th version which is incoming to clean up the design a bit and give me some more internal room. The earpads above are simply stuck on with some blutack so more on that... For the earpad mounting, there two problems there really. None of mounting hardware was included and anybody who had changed the 009 pads knows just how fucking stupid that mounting setup is. I also wanted to use non Stax earpads (not paying 300$+ for pleather crap) so here is what I came up with: Same idea really but I added a spacer between the plate and the driver housing so there is room to slide the lip of the earpads underneath it. The two layers of the PCB sandwich are visible there (along with the production number as I forgot to have it removed) and it works nicely. I could have made this from aluminum but it wouldn't have cost roughly 4$ then... This is the fitment with some random test earpads and standard 1.6mm PCB's. Works just fine and I can't find any issues with baffle seal... quite the contrary really. So here we are, the MA-009 This set of earpads has already been replaced and it takes a matter of seconds to swap them over. What a novel feature... Now what was the true goal for all of this, well besides having some fun doing something new... make a set of 009's I would actually want to sit down and listen to. Now this project is far from over but here is something novel... a SR-009 that has some actual bass output. They are still forward sounding but it has been diminished by a large extent. I can use these for hours quite happily, even at my usually higher volume levels. The decision to use 2um mylar was to try and tame that forward edge and it has been partially successful. A stock set of 009's is terrible on most music I try them with, this one is mostly good with just some tracks which show how bad that stator design really is. There is this slight forward sheen over everything and it simply has to be the stators as the rest of the headphones has so much in common with the 007 overall design. Now the major issue is driver stability as the left diaphragm really likes to get stuck to the stators and I have to open up the driver to get is back on song. I might have gone too far in sealing them up but I wanted some bass dammit!! I will make some more test diaphragms and see if I can make some which can handle the pressure of going on the head energized while giving the sound I want. For now I'll just use this pile of parts to make some music... So to end off... if anybody has a set of 009's with blown drivers that are collecting dust... hit me up and I might want to buy them.

A SRM212 with one of those USB to barrell jack adapters and run it off a normal USB power bank. 4W should be just fine of a 2A output.

Driver size has nothing to do with performance over a certain threshold (say 60mm), I'd even say it makes a lot of parameters much worse. It's more down to the structure design, stator design and diaphragm properties. Stax are failing at all of these BTW... it's all bad. It seems there is very little interest in the 009D, goes to show with the stupid promotion they have running with them. Buy a set in December, mail them a registration paper (as in by post) and they will send you a 1.5m cable. They say it is the silver plated one so why include that and not the OFC as is stock with the phones. Makes no sense.

Same OFC cable I can see and rather underwhelming overall. I didn't bother ordering one but I might if there are any discounts to be had. I have my SR-009 with new diaphragms up and running and it is quite interesting just how badly designed those stators are. Even with new diaphragms tuned to be anything but bright... they are still far too bright. Still far better than the stock unit and tolerable for most tracks... ohhh and they actually have bass now. Odd for the 009's...

Hehe, I don't think I'll ever be there but I have a lot of fun messing with this stuff. I might open this up as a DIY project if anybody is interested as this isn't all that hard to do and no bad chemicals are used. While on the subject, I finally got the last parts to get my reclaimed SR-009 drivers up and running with new diaphragms and dust covers. I skipped straight to the Mk2 version of the main diaphragm rings and they are now sitting on my head with nothing holding the earpads on them and cables just dangling off. I keep reiterating the new cable entry design so I won't post pics until the system is all complete.

Finally the PCB's arrived for the Kiwi Ears headphone drivers: Just three different PCB's needed, on the left is the diaphragm ring which is a 0.6mm pcb but with no solder mask so it is actually 0.51mm. This has to be ENIG to make it completely flat but most fabs require that anyway. Film is 2um mylar-c as that is so simple to get and relatively easy to work with. In the middle is the dust cover holder/spacer. I made this 1.6mm thick as that way it clears the stock lip on the baffle that was around the dynamic driver. I used the first one as spacer and then stacked up the driver sandwich. For the dust covers I used the same mylar as the diaphragms but not stretched as much Finally the stators, 1mm ENIG pcb's and this is the outer side with the inner side having a smaller active area, aka like the SR-007. Holes are a bit less than 1mm but that can easily be altered for another run. Here they are assembled with the only alterations to the baffle where I counter sunk the mounting screws. There were just the three holes there in a row and with the earpad mounting plate being flush to this, it had to be done. One second with a counter sunk bit will do this as this is nasty, cheap ABS plastic. Here they are assembled. Only mods to the chassis is that I enlarged the two holes there are on each side (cable entry and a port on top) to 5mm so the strain relief would fit and the solid plastic plug I glued into where the port is. The cable is the 6 core silicone wire that can be found everywhere now with a 3D printed Y-split and Stax plug made from an XLR plug and pins. Now for the sound... lets just call it work in progress. This is very much the first draft and one channel is slightly weaker than the other (I swapped out the diaphragm for another which fixed it mostly) so I need to look into that. I'll probably just build a second pair of drivers so I can match them into pairs as I have another set of the headphones. Massive baffle leak too and the housing... has issues... so bass is not their strong suit for now. That needs to be fixed but I might have to get creative with that. Still for a cheap project that took only a few hours to make and cost less than 150$ all in... there are worse ways to spend an afternoon.

I always have a ground plane or rather two, on both sides.

They have been officially released now: https://stax.co.jp/product/sr-009d/ List price is 385KYen with the 10% tax so likely in the 340kYen range for street price.

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.