[John Buchanan]

Quote:

I've got a set of Stax SR-202s that need some refurbishment love. The foam inside the earpads has disintegrated, and the headband itself doesn't retain tension.
 
Is there a reputable business or Stax-loving soul out there who can bring these back to ship shape? The US distributor Yama's Enterprises (or Accutech?) gets all kinds of loathing on this forum, so I wasn't keen to start with them. 
 
I'm in the San Francisco Bay Area - happy to ship anywhere (though for these cans not sure it would be worth shiping outside the US).
 
Many thanks for your guidance.

This isn't hard to do yourself.
New pads http://www.audiocubes2.com/product_info.php/manufacturers_id/18/products_id/266
New arc assembly http://www.audiocubes2.com/product_info.php/manufacturers_id/18/products_id/411
The most tedious part is pulling the ear pads off (they are simply stuck on with a sticky double-sided tape) and cleaning the residual sticky material off the hard plastic cases to provide a clean bed for the new ear pads to be stuck on (the newer pads have a separate, non-decomposing type of earpad mesh). 

 

[Talisker10]

Quote:

This isn't hard to do yourself.
New pads http://www.audiocubes2.com/product_info.php/manufacturers_id/18/products_id/266
New arc assembly http://www.audiocubes2.com/product_info.php/manufacturers_id/18/products_id/411
The most tedious part is pulling the ear pads off (they are simply stuck on with a sticky double-sided tape) and cleaning the residual sticky material off the hard plastic cases to provide a clean bed for the new ear pads to be stuck on (the newer pads have a separate, non-decomposing type of earpad mesh). 

Many thanks for the pointer - very much appreciated!

 

[sillysally]

Quote:

Congrats!
 
Yes, yes they are amazing! I'm still amazed at the stuff I'm hearing that I wasn't able to with my previous headphones on some of my very favourite recordings with the SR-009s.

I am glad you hear what I hear with the 009's. But for me what was the best surprise was getting the SRM-727 amp for under 2K new and how really well this amp drives the 009's. Now you know why I say this combo is the end of the line for me. 
 
ss

 

[MacedonianHero]

Quote:

I am glad you hear what I hear with the 009's. But for me what was the best surprise was getting the SRM-727 amp for under 2K new and how really well this amp drives the 009's. Now you know why I say this combo is the end of the line for me. 
 
ss

Hey Peter...agreed. 

 

[arnaud]

The Omega 2 cup is cast aluminum isn't it? A large portion of SR009 parts are milled from aluminum blocs. Also, the 3 layers making each side of a stator are milled/etched before being fused under high temperature / high pressure process ensure a strong bond. From the video interview with the director of engineering, the cost of the 009 stator assembly is 5-10x higher than previous design because of the added steps (3 parts to etch instead of 1 for each stator, high pressure / temperature fusing). Furthermore, the yield is very poor (for the tight tolerancing you mention birgir) so it's no like they will be making cost savings as they sell these for a while. Benefits are a stiffer electrode overall while ensure minimal thickness over most of the surface to increase transparency.
 
I will add to that it appears the 007 was designed under a more stringent cost enveloppe than the 009. The 009 design was aimed for a new category beyond omega 2 and to mark 50th anniversary of first earspeaker release, hence the decision to make a completely new electrode design.
 
 
Here's the original interview video: http://www.youtube.com/watch?gl=JP&hl=en&client=mv-google&v=wKTuBjI4Cp4&nomobile=1
A longer interview here but no additional details that weren't originally provided apart from warranty upon product registration and 009 being easier to drive than previous units so usable with lower end stax amps: http://www.ustream.tv/recorded/13640147
 
Quote:

 
I think it would be better to include the SR-Omega in the comparison as it was priced the same as the 007Mk1 (in Yen which is the only yardstick that matters here).  The SR-Omega has very expensive drivers but the rest of the headphone is far less special.  The drivers have a very fine gold plated copper mesh married to a resin structure at great precision with the dust covers and diaphragm supported on brass rings.  The whole assembly is slotted into a resin frame which makes up most of the earcup with the aluminum simply being a shell around it.  This makes servicing hard and there are some major corners cut (hello Lambda headband asked to support those housings...) to make up for the cost of the drivers. 
 
The SR-007Mk1 has a far better housing and headband/arc design with better materials but the drivers are less OTT.  Now we have a fully milled aluminum cup with the driver fully enclosed in a resin frame which is bolted directly to cup for excellent transfer of energy.  The SR-Omega isn't nearly as well constructed in this regard which can be clearly heard at higher volume levels.  The headband is a work of art as it's very cheap to build yet allows unlimited adjustment.  Better materials all around (especially on the later units) but the drivers use PCB material for stators, diaphragm supports and the dust cover rings.  PCB's can be mass produced in large quantities at very high precision plus they are non resonant and very strong.  It also allows to place with openings and where they are placed.  Granted etching copper or brass does allow for this as well but they have their own issues. 
 
With the 009 we have the marriage of these two design principles, expensive housing with a very expensive driver and naturally, double the price.  The housing follows the same principles as the SR-007, milled aluminum though I know they looked into cast magnesium for the frame but it was ultimately too expensive.  It's not as substantial as the 007 housing though.  The driver uses the same resin frame as the 007 but all the parts are high precision metal.  The stators use three pieces bonded together to make it very stiff and strong plus they looked into the thermal issues quite a bit (009 driven hard can dissipate close to 1W in heat, so much for electrostatics not needing power) as the stators could get warped a tiny bit which will increase distortion.  One has to remember just how tight the tolerances are here as the total stator to diaphragm gap for Pro bias is 0.5mm or 500um.  That's very, very small indeed...  As much as I hate the 009 headband it isn't cheap to make even if it is a bit flimsy.  The 009 design also almost bankrupted Stax so that's probably why they made them so bloody expensive.  Such a shame they can't live up to their potential though... 

 

[spritzer]

You can see the machining marks on the Mk2 sets (the black contrasts them) so they are not cast.  The coating used on the Mk1's is very thick so it hides them nicely. 

 

[milosz]

Quote:

 
SR-007Mk1 .... Better materials all around (especially on the later units)

 
 
Do you know approx what serial number the "better materials"  began being used?  And better materials- which materials?  Stator 'boards'? - diaphragm material?- diaphragm coating?- dust cover material?
 
I'd be curious as to how the SR-007 driver differs from Lambda series construction, too, in general terms.  Do Lambdas also use PCB material as stators?
 
----------
 
Thanks Spritzer.  Lots of info in your post.

 

[milosz]

Quote:

I've got a set of Stax SR-202s that need some refurbishment love. The foam inside the earpads has disintegrated, and the headband itself doesn't retain tension.
 
Is there a reputable business or Stax-loving soul out there who can bring these back to ship shape? The US distributor Yama's Enterprises (or Accutech?) gets all kinds of loathing on this forum, so I wasn't keen to start with them. 
 
I'm in the San Francisco Bay Area - happy to ship anywhere (though for these cans not sure it would be worth shiping outside the US).
 
Many thanks for your guidance.

I've replaced earpads on a couple of pair of Lambdas.  There are some tricks.  First is to clean off all the old adhesive. The earpads are just stuck on with a film of sticky stickum. So, you peel the old earpads off, using a little force, and that leaves a bunch of adhesive on the earcup face.  Some, you can scrape off with a razor.  But I think to get it all you need a solvent.  I used "Goof Off" solvent on cotton rags; paper towel will just come apart. First, I made a rag wet with the solvent then carefully dabbed solvent onto the old adhesive, and let it sit a minute to soften the adhesive.  Then I moved to a rag that was damp with solvent but not wet, you certainly don't want Goof-Off solvent pouring down into the driver itself.  After some rubbing, little additions of solvent, moving to new parts of the rag, etc, the face eventually gets 100% clean.  The earcup inner foam- which is usually perished - is either totally gone having crumbled to dust, or you can discard any of it that is left.  The new earpads come with a cloth inner cover which will last much better.
 
Be careful placing the new earpads-  after you peel off the protective layer on the adhesive you get ONE CHANCE to place them properly.  Be aware that they have a front and a back- the earpads are thicker where they go behind your ear.

 

[Nemeske88]

Dear Forum(ers)!
 
I am new to the STAX earspeakers and something caught my attention.
I have a sr-303 and yesterday I was checking the ebay for other Lambdas when I found that the former Lambda models have a different diaphragm material ( or color or just a look )
See at this Picture  than my stax sr-303.
 
Can anybody tell is there a difference in the diaphragm molding technology or it is just the ,,protecting net" that do not allow to see the oscillatory film at the 303s?
 
Yes, this is very pointless question but I am so curious
 
Than you for your answer

 

[milosz]

Quote:

Dear Forum(ers)!
 
I am new to the STAX earspeakers and something caught my attention.
I have a sr-303 and yesterday I was checking the ebay for other Lambdas when I found that the former Lambda models have a different diaphragm material ( or color or just a look )
See at this Picture  than my stax sr-303.
 
Can anybody tell is there a difference in the diaphragm molding technology or it is just the ,,protecting net" that do not allow to see the oscillatory film at the 303s?
 
Yes, this is very pointless question but I am so curious
 
Than you for your answer

 
What you are seeing on that old Lambda is the metal mesh that keeps your ear and other things from actually touching the driver, which is further inside the earcup. It's just a protective screen that you see, not the driver.
 
That old Lambda USED to have a thin sheet of black foam covering that metal screen.  Over the years, the plasticizers in the foam evaporate & oxidize and the foam crumbles to dust.  It just falls apart and is gone.  Your newer sr-303 either has the foam cover layer still intact or perhaps it uses the newer style of cover, which is made of black cloth.  All foam eventually falls apart, but the newer cloth covers should be very durable.
 
The foam or cloth cover is mostly cosmetic and has no electrical or acoustical function.  I suppose it does absorb a little sound, but it's purpose is to look nice and add a little comfort.  Maybe it protects the works a little from dust too.

 

[spritzer]

Quote:

 
 
Do you know approx what serial number the "better materials"  began being used?  And better materials- which materials?  Stator 'boards'? - diaphragm material?- diaphragm coating?- dust cover material?
 
I'd be curious as to how the SR-007 driver differs from Lambda series construction, too, in general terms.  Do Lambdas also use PCB material as stators?
 
----------
 
Thanks Spritzer.  Lots of info in your post.

 
No idea when the change occurred but it was sometime around the 71xxx roll around.  Better materials include better faux leather on the arcs, better headband but they also also did some not so well thought out changes to the drivers. 

 

[K_19]

Very interesting... Mine's #71009 so it's right near that uncertainty mark... my materials seem fine though and sounds great, so nothing more that I can ask for 

 
BTW, any tips on best ways to take care of the default O2 MK1 pads? Would like to try MKII pads someday, but the default ones came to me in great shape and I'd like to keep it that way for as long as I can...

 

[spritzer]

Just clean the pads with mild soap and water.  I have one of the first 007's here with the stock pads and the leather is still fine.  The foam is beyond perished but it only lasts a few years so that is to be expected. 

 

[Tubebabe]

Quote:

I just acquired a Stax SR3 and SRD-5 on eBay so I'm joining the Head-Fi club now.   Unfortunately the "works great" e-Bay headphones do so only for the first 3 minutes or so and then the left ear starts slowing fading down in volume until the balance control on my preamp needs to eventually end at full rotation after about 10-15 minutes.
 
I've tried pumping high volume pink noise through it overnight and that only made it sound distorted when I first tried it in the morning and then it faded out again.
 
Is this a common problem? I'll likely change out the capacitors in the SRD-5 but I suspect the fading is from the SR3's.
 
The fading out of the left earspeaker starts within 30 seconds of listening.
The one minute of music does sound great though! If I follow the fading with the balance control on my preamp, I can get a full song and I am happy with the performance.
 
I tried unplugging the SR3's and shorting all the pins to discharge residual charges and then plugged them back in; still weak on left ear.
 
If I leave it for a few hours and come back, balance is now good and then starts to fade again as music is played.
 
If I need to open up the SR3, does anyone know of any instructions on the web on how to do this properly and safely?
 
Any suggestions from the vintage Stax guru's?
Thanks in advance for any help you can give.
 
 
 

I'm not feeling the love...    
Seriously, is there anyone here familiar with SR-3's or did I make a mistake buying too old?  I'm "vintage" myself so I like my equipment to come from the same era.
Is this a known problem with one earspeaker fading out each time it is used?
 
Thanks.

 

[Amarphael]

Quote:

 The foam is beyond perished but it only lasts a few years so that is to be expected. 

 
If indeed the foam material has this short life-span, won't Stax refurbish the foam if one is to send them such a pair of pads? I mean, It's very nice thing to do from the perspective of recycling and good cutomer service (at a cost no doubt) for a premium product. I won't mind paying, say, 2/3 of the price of a new pair for such a service.