Kevin is indeed full of surprises... 

As for the 009, I think a lot of them experience some charge issues.  My current set did so I just hit it quite hard on the offending channel.  Right as rain after that. 

I'm a firm believer in showing products who's boss.

4 hours ago, spritzer said:

 Right as rain after that. 

 

If the diaphragm is stuck to a stator then yeah, we need to show it who's boss!! 

Hell you are THE DUDE, I just smacked my 009s on the left frame and it seems to have worked. My goodness!!!!!!! My hand still hurts though.

I showed it who's boss alright, smack that bitch up.

Now to run them overnight and see if it is all ok.

You know, this could be the reasons why many are getting the imbalance and get 'fixed' on the flight back to Japan? All the pressurisation and slowly reducing to normal atmospheric (plain lands). Well my plain has landed, nice, no go grab me a Rammstien track and turn it up. Oh life is worth living isn't it?

Edited April 5, 201610 yr by astrostar59

... smack the phony, then there are no turning back ... sorry to hear about your hand, building pressure too fast might give a burning sensation

Hmm might have spoken too soon. The volume on the left side is still down about 5-8% I estimate. Enough to make me feel like I am falling over to the right side.

The right frames vibrated more than the left on bassy tracks as well so I not imagining it.

I will need to send them in for a warranty claim I think. No sense in hoping it resolves itself. I have 6 weeks of warranty left luckily.

I hope the Stax service are on board with it. Lets face it, they are 3K headphones, makes no sense to accept an imbalance this big. OK it's not 50% out to a failure,

but kinda ruins the stereo image.

 

It does make you wonder STAX's move to PEEK film rather than their tried and trusted mylar is behind some of this erratic behaviour.  

Looking at the material properties alone, PEEK is higher performance in pretty much all areas, so I can see from an engineering perspective why the change; water absorption alone is 0.1% as compared with 16% for mylar, which might be thought rather important for a component in an electrostatic transducer.

But there seems to be a few reports of degraded performance over time - either sticking to a stator, or a drop in sensitivity of one side.  The only mechanism I can think of is that the film is not getting enough charge so the force drops, so maybe it is not the mechanical properties that are so important and it is down to the processing detail of applying a highly resistive film and making a reliable contact to it.  I had a pair of Martin-Logan speakers that happened to - the connection to the film failed.

 

The film is attached to a large metal ring (that's how Stax have been built since day one) but we could be dealing with a connection issue as to how the cable attaches to the ring.  I've never opened up a 009 so I can't be sure.  It could also be an issue with the coating or the film tension. 

If anybody has a broken 009 then I'd love to buy it.   

Interesting points on here. I wonder if the 009 drivers (out of warranty of course) are user repairable? I spotted an old thread on the earlier Stax drivers and they seemed to come part ok. It is on page 409 of this thread.

Sure, they can be repaired but you will have noise issues unless you just happen to have a working cleanroom... 

Finally found a pair of HE90s (more for the novelty than anything else).

 

Reading some mixed reports about the HE90->Stax Pro adapter spec -- should the bias line include a 10M ohm resistor or is 5M fine? The HE90 is from the pre-Meier series (no bias-reducing tweaks) and I'm going to use it with the BHSE.

 

I suppose I could try changing the bias voltage from the BHSE PSU but that's way out of my depth and I love the SR-Omega too much to bother.

You should add a 5M resistor in series with the bias line.  The Stax output has a 4M7 resistor on it so you need the extra 5M to meet the Sennheiser spec. 

Thanks Birgir.

Do you think 4.7M-ohm would be "close enough"? I have the opportunity to purchase such an adapter pre-made, or have a new one made for slightly more. I'll obviously spring for the extra $$/time if the 0.3M-ohm makes a meaningful difference in not destroying the HE90 out of the BHSE...

Nah, it will be close enough.  Just made sure the resistors is a high voltage unit rated for at least 600V. 

Got my first Electrostatic setup (Stax SRM 1/MK 2 [Spritzer Mod] + Stax SR 407) and I've got to say Stax SR 407 has quite a bit of bass (More than I was expecting to be precise), in fact it has more bass than the AKG K340. Jazz, Western Classical, Folk, Indian Classical, Blue Grass seem to have a good pairing with this combo. Currently setup 3 is my favorite which is closely followed by setup 2. 

Setup 1- PC +J River 21 + Resonessance Labs Concero HP 

Setup 2- Macbook Air Haswell + Amarra Symphony + Resonessance Labs Concero HP

Setup 3- Questyle QP1R 

  

 

Been pondering this issue of problems with the SR-009 (mainly and possibly a few 007).

I have just acquired a new L700 and the instructions say "avoid using earspeaker in a hot and humid conditions", without any specific guidance.

Well I wouldn't use them in the bath, but all my listening is done in England where the rooms are about 20c (68F) and dry.  I have never had a problem with my Staxes.

What is considered opinion of what is too hot and humid for Stax ES?  

And by inference any possible connection with problems people are having?

Edited April 11, 201610 yr by headinclouds
sp.

3 hours ago, xEcuToR said:

Stax SRM 1/MK 2 [Spritzer Mod]

What is the spritzer mod?

^ I've heard it involves Viking urine.

^Every time - every damned time - you reduce me to gales of laughter 

Only the special edition mods feature that and well you can guess what the reference series of mods entail...

Btw.  Did any of you see the NOVA episode last week where they might have uncovered another viking settlement in Canada?  Truly epic stuff and it also mean we own you bitches...   

2 hours ago, headinclouds said:

Been pondering this issue of problems with the SR-009 (mainly and possibly a few 007).

I have just acquired a new L700 and the instructions say "avoid using earspeaker in a hot and humid conditions", without any specific guidance.

Well I wouldn't use them in the bath, but all my listening is done in England where the rooms are about 20c (68F) and dry.  I have never had a problem with my Staxes.

What is considered opinion of what is too hot and humid for Stax ES?  

And by inference any possible connection with problems people are having?

The instruction manuals have always stated that though it was something like 90% but non condensing.  Change the humidity and you change the breakdown voltage of the air dramatically.  Normally it is around 100V/mill so the drivers are setup around that though with plenty of headroom. 

I don't think humidity is the culprit in the recent driver failing though.  It might contribute due to its effect on static charges and stuff like that but at the end of the day the drivers just aren't stable.  Being able to restore them to full operation by hitting them is a giant red flag to this fact. 

1 hour ago, cetoole said:

What is the spritzer mod?

Converted to balanced operation. 

With balanced lemo connectors on the back?

5 hours ago, swt61 said:

^ I've heard it involves Viking urine.

Hopefully not with the unit turned on - peeing on a high voltage amp could be....interesting.

6 hours ago, spritzer said:

The instruction manuals have always stated that though it was something like 90% but non condensing.  Change the humidity and you change the breakdown voltage of the air dramatically.  Normally it is around 100V/mill so the drivers are setup around that though with plenty of headroom. 

I don't think humidity is the culprit in the recent driver failing though.  It might contribute due to its effect on static charges and stuff like that but at the end of the day the drivers just aren't stable.  Being able to restore them to full operation by hitting them is a giant red flag to this fact. 

Yes thanks Birgir, that was what I was looking for.  So possibly the large diaphragm and small spacing is more prone to this.

Diaphragm size and the D/S gap are the same or similar as on other models such as the SR-Omega so that isn't a factor.  There are really only two variables here, coating material and the diaphragm tension. 

 

8 hours ago, DefQon said:

With balanced lemo connectors on the back?

I think so, can't remember... 

6 hours ago, JimL said:

Hopefully not with the unit turned on - peeing on a high voltage amp could be....interesting.

When tweaking we have to take risks!!  Next step is submerging it in molten lava!!