[cucera]

Well I guess it will be more than a year from now before we can confirm this assuption if the change was recently. Even when someone buys a new one now, nobody will now weather it is the newest charge or has been at the distributor for a while as Stax is not using linear SN.

 

[TheAttorney]

  This debate about 009's and any changes. Can't somebody just ASK THEM! Or are Stax one of these folk who just don't pick up?

Manufacturers in general wouldn't necessarily answer such a question honestly. They'll give you the answer that fits in with whatever communications policy they may have.
 
Secondly, the person you ask will not know all that is going on in the lab.
 
Thirdly, some changes might be considered inconsequential to SQ by the company (eg. change of quality of leather on pads, as per Zolkis comments).
 
Finally, it may be nothing to do with old or new. There may be a level of sample variation. I.e. this is a precision instrument at least partly hand made. So it is quite conceivable that sometimes one will be slightly different to others.
 
Finally, finally, this may all just be over imagination. All I can say is that my brand spanking new (not been waiting in a distributors warehouse) 009s do not suffer from over brightness compared to my 007 Mk1s. I'm delighted with that aspect. I should add that my hearing tails off after 13kHz, although in the past all "brightness" issues for me have come in at much lower frequencies than this, starting with the upper mids.

 

[cucera]

Stax especially is secretive with the changes. They even didn't acknowledge the massive change of the 007 in 2011 when they used a new Diaphragm material and still call it MK2 instead of mk3. It is practically a new headphone as much changed as 404 to 407.

 

[padam]

But they did change the series to SZ3 instead of SZ2.

 

[Michgelsen]

And do they even speak English over at Stax..?

 

[NoPants]

That's not really an issue for a handful of people here, but it's more that no one's going to admit to intentionally creating variability and changes in their product.

 

[Earspeakers]

Undocumented minor product revisions are a fact of life folks, everybody does them. 
 
At my job we invent and sell hardware devices (I write the software for them) that cost 20X the 009's, and they frequently get unannounced changes and improvements in between major revs. 

 

[Jones Bob]

It may be as simple as thier prime vendor discontinuing supply of the diaphragm raw material. Going to another source with a near equivalent material could lead to a slightly altered SQ. Unplanned unexpected consequences.

 

[n3rdling]

Very unlikely that they ran out of super engineering plastic.  Minimum quantity with the places that make this stuff is at least a roll, which is usually over 3,000 ft...in most cases way more.  I also don't think we should state that the diaphragm on the 007 SZ3 is a different material than the SZ2 unless we have evidence, as far as I know it's still simply speculation.

 

[Currawong]

If there was a change, it would most definitely be deliberate I reckon.

 

[Earspeakers]

It may be as simple as thier prime vendor discontinuing supply of the diaphragm raw material. Going to another source with a near equivalent material could lead to a slightly altered SQ. Unplanned unexpected consequences.

Exactly, particularly with small time manufacturers like this. Only the big ones like Apple can really secure their supply chain, small guys are much more subject to obsolescence issues. 
 
That's particularly the case with electronic components but less so with Stax though, I would think. 

 

[HemiSam]

I posted the following in the entry level Stax thread also, so please forgive if you're seeing this twice:
 
I don't know if I'm posting in the right thread, so apologies up front if I'm in the wrong place.
 
I took a dive into electrostat hp's with the purchase of Koss ESP-950's along with the E/90 amp.  Been very much enjoying the detail, highs and mids since I purchased them a few weeks ago.  Currently revisiting my Led Zep collection...sounds great  I've not been listening to my other rig since then and have been looking at an amp upgrade for the e-stats.  The Stax SRM-1/MK-2 looks to be a good one based on several threads I have been reading through.
 
My question:  is this indeed a good choice for an amp upgrade without breaking the bank and if so, the Stax amps I have seen obviously have quite a few years on them.  Is there a trustworthy technician/elctronics store in the U.S. that specializes in tune-ups and restorations so I can have a purchased SRM-1/MK-2 refreshed to ensure I have a good working unit?  I would also ask the shop to modify the Koss extension cord with a Stax plug to allow me to use the ESP-950s with the upgraded Stax amp.  
 
Thanks for any thoughts/recommendations.
 
HS

 

[Ali-Pacha]

Sorrodje has precisely this pitch of yours...except he's from France. You may find him on the HD-800 thread 

 
Ali

 

[HemiSam]

  Sorrodje has precisely this pitch of yours...except he's from France. You may find him on the HD-800 thread 

 
Ali

 
 
Thank you, Ali.  Sorrodje and I have communicated on this topic...very kind and helpful gentleman.  Given he is located in Europe, he is taking a path that would be too pricey for me (i.e. sending my equipment to Europe from Texas).  So I'm hoping I can find a good tech/shop domestically.
 
I have found a thread on how to change the caps here, and while I do have a soldering iron and do some electrical work on my race car, I am a bit of an oaf/rough with the equipment...much better with mechanical items.  So I would prefer to find someone that knows what they're doing and has a more delicate touch.
 
HS

 

[b0bb]

  I posted the following in the entry level Stax thread also, so please forgive if you're seeing this twice:
 
I don't know if I'm posting in the right thread, so apologies up front if I'm in the wrong place.
 
I took a dive into electrostat hp's with the purchase of Koss ESP-950's along with the E/90 amp.  Been very much enjoying the detail, highs and mids since I purchased them a few weeks ago.  Currently revisiting my Led Zep collection...sounds great  I've not been listening to my other rig since then and have been looking at an amp upgrade for the e-stats.  The Stax SRM-1/MK-2 looks to be a good one based on several threads I have been reading through.
 
My question:  is this indeed a good choice for an amp upgrade without breaking the bank and if so, the Stax amps I have seen obviously have quite a few years on them.  Is there a trustworthy technician/elctronics store in the U.S. that specializes in tune-ups and restorations so I can have a purchased SRM-1/MK-2 refreshed to ensure I have a good working unit?  I would also ask the shop to modify the Koss extension cord with a Stax plug to allow me to use the ESP-950s with the upgraded Stax amp.  
 
Thanks for any thoughts/recommendations.
 
HS

The SRM-1 is getting quite old and will at least need to have the capacitors replaced and the balance and offset re-adjusted to account for ageing.
 
An alternative is the SRM-323s, this is a current production model and a used model can be had for about $150-$200 more than the SRM-1 based on a quick look on Ebay.
A new SRM-252s for about the same price from places like PriceJapan.
 
The SRM-252s runs at a lower voltage and does not play as loud as the 323s, works well if the 12V wall wart is replaced with a real regulated PSU.
 
I own both of them.