[soren_brix]

  Hi All
I have a 23 month old 009 I bought from a dealer in the UK. It has developed a marked channel imbalance. I have thus sent it to the service centre in the UK.
 
My question, does anyone know if they would replace the problem driver, or both, or replace the whole headphone?
 
I am unsure if a new driver would match the existing one that is ok. Stax do change production over time, and I can see a new driver would not match.
 
I have read some guys on here had issues with their 009s and as that happened soon after purchase i.e. 2 or 3 months, they got a new pair.
 
Any help would be great. I am hoping they don't need to go back to Japn, I am missing them already!

 
 

  Quote:
My - much cheaper - SR-303 needed a driver replacement a couple of times. The service guys have always replaced both drivers, they are matched. Your SR-009 will  certainly get both drivers replaced.

 
I asked Electromod in UK, and was told the same, both drivers are replaced as they are matched.

 

[astrostar59]

   
 
 
I asked Electromod in UK, and was told the same, both drivers are replaced as they are matched.

Thanks guys. I hope that is the case. Thing is it isn't just the sound level but the frequency response as well, stuck pn your head you can tell really easily if they are out of parity.

 

[goobicii]

in what way is Woo Wee energizer detrimental to the sound quality? if you pair it with speaker amp that is same or better quality equivalent of things like T2 diy or kgsshv then wouldnt it be just as good as using mentioned amps?
 
this Stax L700 looks very nice but I dont feel like dropping 4 and half K on Mjolnir Carbon amp when I already have super delicious high end speaker amp

 

[Michgelsen]

While I have never tried transformer boxes, and it goes against my principle and also against etiquette to comment on things I haven't heard myself, I'll say the following to give Stax noobs some general information: people have reported that transformer boxes do the dynamics very well, and can sound good in general, but are outclassed by the direct-drive electrostatic amps in other areas, such as details and control.
 
I'm not sure what's up with the Woo Wee's bias resistor, and whether it is really too low in value, or whether this has been fixed in current-production models. It's always a safe bet to go with the old Stax transfomer boxes. The normal bias ones are usually much cheaper than the pro bias ones, and if you ask Birgir (a.k.a. Spritzer, via mjolnir-audio.com) nicely he could maybe sell you a small pcb to upgrade it to pro bias. He used to sell these boards in the past. You can thus upgrade a normal bias transformer box to a pro bias one. The transformers inside that do the actual work are the same. It's only the bias supply that needs to be different.

 

[goobicii]

I wonder,how many watts from conventional speaker amp would I need to run Stax headphones directly? lets say you have 1000w monoblocks,could it work?

 

[soren_brix]

  I wonder,how many watts from conventional speaker amp would I need to run Stax headphones directly? lets say you have 1000w monoblocks,could it work?

as Michegelsen point out many has been satiesfied with a transformer solution despites its limitations.
The SRD-7 is a good choice.
If you want better a pair of Lundahls LL1630 would do the trick, but you'll be looking at +300EUR (the cost of the last pair I bought) and need to add BIAS supply and chassie.
You don't need much power ... you can wire the LL1630 to have lower ratio and thus need more, but nothing a modern amp can't supply. 100W monoblocks will do fine in either case.

 

[goobicii]

  as Michegelsen point out many has been satiesfied with a transformer solution despites its limitations.
 

 
what kind of limitations are we talking about? will the transformer add harmonic distortion? noise? phase shift?? I still dont get what exactly in scientific terms happens to a signal from high end speaker amp that will in the end make it inferior to dedicated stax amp like bhse for example

 

[Michgelsen]

Limited frequency response at the extremes for one. Also, limited power handling. Usage with 1000W monoblocks is not advised.

 

[Crashem]

  in what way is Woo Wee energizer detrimental to the sound quality? if you pair it with speaker amp that is same or better quality equivalent of things like T2 diy or kgsshv then wouldnt it be just as good as using mentioned amps?
 
this Stax L700 looks very nice but I dont feel like dropping 4 and half K on Mjolnir Carbon amp when I already have super delicious high end speaker amp

 
The information you seek is around and the information seems obvious to experience stax guys.  Hence you are getting a bit of teasing.  To simplify things, the needs of a good electrostatic amp are different than a dynamic (current) amp.  Designed for two different things.  Think truck vs sports car.  Electrostatic amp needs to do huge voltage swings and little current.  While a good dynamic amp, needs to produce both current and voltage.
 
So what does the energizer do?  It uses a transformer to convert current to voltage.  So if the transformer isn't good enough, it will limit things.  Again to use the truck/car comparison, just because you use device to convert the power of a big truck engine to generate speed doesn't suddenly make that truck a sports car.
 
Read post #65 of following post from Spritzer, acknowledge expert in all things stax:
 
http://www.head-fi.org/t/504471/wee-new-product-from-woo-audio/60#post_6886820

 

[bnsb]

I have bought a Stax SRS 4170 Ear-speaker system by direct import from Japan. The unit I received naturally was set to 100V. Thanks to input from posters here in particularly Spritzer, I could get the input voltage changed to 230v. It took a qualified engineer 4 hours plus. Blew the fuse twice - the unit not engineer - the engineer was cool Heard Stax for the first time in my life, Unbelievable experience. Thanks also to huge repository of knowledge shared here.

 

[Michgelsen]

It's good to hear that you like it, and that it's still possible to rewire Stax amps.

 

[bnsb]

Trust me it was 

  It's good to hear that you like it, and that it's still possible to rewire Stax amps.

Trust me rewiring was tedious and nerve wracking. Luckily the guy who did it all like I said was thorough.

 

[oogabooga]

I had a chance to demo SR-407 and SR-507 at a local dealer today, using an SRM-727 amp and my Concero DAC. I could not hear a difference between the two, even after going back and forth extensively. 
 
I have a large head (hat size 8) and the 507 were much more comfortable. I was only on position 7 of the 10-position slider, and the clamping force was just slightly more than my old Lambda-Pros, which is to say comfortable for long listening sessions. The pads are very nice, too. The 407 were quite tight on my head (not as bad as the SR-007, but close) and my right ear was just grazing the black fabric over the stator. 
 
They sounded good - I only held off because the L700 is not so far away from the 507 in price, and I want to hear them first.

 

[zolkis]

Would this amp work well with the 007A? http://knob.planet.ee/amps/staxneb1/staxneb1.htm

I have heard that combo and yes it works, at least as well as with the 007t.

 

[zolkis]

in what way is Woo Wee energizer detrimental to the sound quality? if you pair it with speaker amp that is same or better quality equivalent of things like T2 diy or kgsshv then wouldnt it be just as good as using mentioned amps?

this Stax L700 looks very nice but I dont feel like dropping 4 and half K on Mjolnir Carbon amp when I already have super delicious high end speaker amp

IMHO if you use a high end speaker amp together with a good quality transformer solution like Mjölnir Audio, or even the SRD7 Pro, that would be plenty good enough to drive the L700, and it would also tame the highs into a safely polite range from borderline rough.