Awesome. Congratulations, Chinsettawong, incredible job you did there

Now that I'm all pumpped up, just wait and see my new version of Float style headphones.

Bring it on! I really really liked the previous version you had sent over (as everyone who listened to it too), what is evolving in the design?

I am still a bit puzzled about why only changing the cloth cover affected the tonal balance so much on the "current" version, maybe the measurement will illustrate the difference. Having said that, now that Tyll as a kick-ass stat amp, that is a faster method and result much more useful data point .

If I may suggest something on the float replica, try either to add a bit less acoustically transparent screen to tame the upper mids/highs or some other way to reduce front/back wave cancellation so as to get a bit more bass presence. The larger baffle doesn't seem practical, but maybe a way to decrease the distance from ears to electrode?

Last, I can't wait to hear any of you power angry phones through the bhse, that would certainly also change the perceived response I bet!

Cheers, arnaud

amazing job on those headphones.

where did you get the male stax jacks?

amazing job on those headphones.

where did you get the male stax jacks?

 

Thanks Kevin.  I made the male jack by myself since I can't find any good ones around.  I have to sacrifice 2 pieces of XLR male jacks to make one Stax jack.  I take out the pins and put them on my CNC drilled bakelite piece, epoxy them, and put them in the XLR jack frame.

 

 

Bring it on! I really really liked the previous version you had sent over (as everyone who listened to it too), what is evolving in the design?

I am still a bit puzzled about why only changing the cloth cover affected the tonal balance so much on the "current" version, maybe the measurement will illustrate the difference. Having said that, now that Tyll as a kick-ass stat amp, that is a faster method and result much more useful data point .

If I may suggest something on the float replica, try either to add a bit less acoustically transparent screen to tame the upper mids/highs or some other way to reduce front/back wave cancellation so as to get a bit more bass presence. The larger baffle doesn't seem practical, but maybe a way to decrease the distance from ears to electrode?

Last, I can't wait to hear any of you power angry phones through the bhse, that would certainly also change the perceived response I bet!

Cheers, arnaud

 

Hi Arnuad,

 

I have an idea that I would make the the driver's width a little smaller and increase its length just a little so that the total drive area is the same.  What I've found when making the previous pair is that I can't tension the diaphragm just enough so that it has good bass and good stability.  At the end, I have to put a little more tension on the diaphragm and add extra 0.1 mm spacers to make it stable.   I think the main problem is that the driver is just too large for 0.5 mm spacer.  By decreasing the width I mean to reduce it only by about 2 mm.  This 2 mm can make a big difference in stability of the diaphragm, I think.  I'll also try to incorporate a big hole in the center of the driver similar to Stax SR009.  Let's see if it helps with the stability issue.

 

About the Float clone that is with you now, I'm puzzle to hear that you find it so much different than the last time it's with you.  All I did before sending them back to you was to clean them and reglued the front cloth.  The headphones require a muscular amplifier though.  They sound pretty good with my KGSSHV and DIY T2.

 

Wachara C.

I haven't had the pleasure of listening to these phones. Hopefully they will make it to a meet stateside someday.

Edited June 21, 201412 yr by eggil

I second that.  if you need someone to be responsible for them at the next Rocky Mountain Audio Fest, I'd be happy to do so.  I'll be attending this year's Canjam there, and I have a reasonably good reputation around here.  I won't have an amp with me, but I'm sure Justin will be there with a BHSE.

Amazing stuff, surprised at how the measurements turned out. Can a near identical to spec HE90 or Omega1 driver be fabricated?

Thanks Kevin.  I made the male jack by myself since I can't find any good ones around.  I have to sacrifice 2 pieces of XLR male jacks to make one Stax jack.  I take out the pins and put them on my CNC drilled bakelite piece, epoxy them, and put them in the XLR jack frame.

 

 

Way simpler than what I was going to do.  I was going to machine the pins from scratch.

I will do it your way.

This looks as thought its being made out of the AudioValve RKV impedancer? http://www.ebay.co.uk/itm/Stax-headphone-all-series-highend-step-up-transformer-/171364028043?pt=DE_Elektronik_Computer_TV_Video_Elektronik_Verst%C3%A4rker&hash=item27e6178e8b

 

 

Step up transformer for Electrostatic headphones (just like Stax - etc.) include in the setlist. The name of this model is EST. It can be powered from 8 ohm amplifiers, but particularly also from the OTL output of the RKV 2 + 3 (100 Vpp). The device provides both the required for the operation of the headphone-static voltage of 280 / 580 VDC, and up to 550 Vrms signal voltage. The bandwidth achieved while nearly 100 Khz.
This box is ideal for owners of all kind of STAX electrostatic headphones. The combination of RKV Mark 2 and this box give an impressive authentic sound that was perhaps never previously been achieved so. But how can that be, you might ask ... Well, quite simply. In general, the output transformers do indeed known to the problems.
In the EST box but this is quite different. If one uses preferably the RKV
Of course, the output transformer of the company have Pikatron little stray - inductances / capacitances, but the extremely low impedance output resistance of the RKV prevents its adverse effect on the sound.
For this reason, it is almost a must, this combination - to listen RKV / EST.
The EST does not require a separate supply voltage and gains required for the STAX static high voltage elegantly from the signal. A separate supply voltage is always fed possible cause of interference and should if possible be used. as a driver with its output voltages of up to 80 Vpp, a sufficient translation of the transformer of ratio 5 In addition, the exchanger is designed as autotransformer - galvanically coupled.
 

 

specificationsAudioValve: "EST -Box"

-Suitable for low-dyn. Headphones and electro-static headphones just likeSTAX
-3 switchable mode for-"8 ohm"-"32 ohm"-"electrostatic mode"
- Mode for down step ratio(dynamic headphones) and step upratio
-Quality Pikatron output galvanic coupled transformers
-Combi jack sockets for dyn. headphones and all STAX headphones models
- No interfering external power supply nessesery
- Internal bias voltage for STAX280+580VDC (LED control)
-Suited perfectly in interaction with RKVMark 2
-Can also be connected to semiconductor amplifier

here in thepicturethe excellenttransmission propertiesof theEST used on aSTAXheadphoneconnected to theoutputof the RKV Mark 2

 

Edited June 21, 201412 yr by complin

Congrats on the recognition Wachara.  You deserve it

 

Thanks Kevin, Birgir and Tyll for your collective efforts.  It's really nice to see some measurements.

I haven't had the pleasure of listening to these phones. Hopefully they will make it to a meet stateside someday.

 

I second that.  if you need someone to be responsible for them at the next Rocky Mountain Audio Fest, I'd be happy to do so.  I'll be attending this year's Canjam there, and I have a reasonably good reputation around here.  I won't have an amp with me, but I'm sure Justin will be there with a BHSE.

 

No problem!  Please PM me your address and I'll gladly send the phones to you. 

Amazing stuff, surprised at how the measurements turned out. Can a near identical to spec HE90 or Omega1 driver be fabricated?

 

Tensioning of diaphragms plays a very critical role here.  In my opinion, it's even more critical than making the stators exactly the same as HE90 or Omega 1.  

Very awesome, Wachara. I haven't followed the DIY stat thread on HF in a very long time, do you still use the knocking against table method to match the tensions or some other way?

Spritzer or anybody that own/ed a 4070 any internal shots of the driver chamber and port? Really interested in what the inside of the 4070 looks like.

I second that.  if you need someone to be responsible for them at the next Rocky Mountain Audio Fest, I'd be happy to do so.  I'll be attending this year's Canjam there, and I have a reasonably good reputation around here.  I won't have an amp with me, but I'm sure Justin will be there with a BHSE.

 

Tyler, my son and I might be able to make room for you at the Marriott if you need a place to stay for RMAF.  I invited Blutarsky but not sure he can make it.

I appreciate it, Larry, but at that point my daughter will be less than a month old.  I presume my wife would like me to find my way home to COS every night

Spritzer or anybody that own/ed a 4070 any internal shots of the driver chamber and port? Really interested in what the inside of the 4070 looks like.

 

I had a pic of it somewhere but I can't find it.  Basically it's a slot cut into the edge of the baffle on both sides that tapers off a few mm from the end.  The pads then partially close it. 

I had a pic of it somewhere but I can't find it.  Basically it's a slot cut into the edge of the baffle on both sides that tapers off a few mm from the end.  The pads then partially close it. 

 

Here you go

 

Is there any opening at all at the back?  The damping material looks to be quite thick.

Very awesome, Wachara. I haven't followed the DIY stat thread on HF in a very long time, do you still use the knocking against table method to match the tensions or some other way?

 

I stretch a larger piece of Mylar that is enough for making a pair at one time, and they seem to match one and the other well.  And yes, I still do the sound checking by knocking them against the table. 

following chinsettawong's idea ...

 

http://gilmore.chem.northwestern.edu/staxmale.jpg

 

will make more once I get some real Teflon. Plexiglass does not

like to do this.

Hmmm my HE90 needs a new plug... 

 

Is there any opening at all at the back?  The damping material looks to be quite thick.

 

No opening and the damping is a thicker type of wool than the one found in the Sigma.  The real start here though is the housing, it took real skill to design something like that. 

following chinsettawong's idea ...

 

http://gilmore.chem.northwestern.edu/staxmale.jpg

 

will make more once I get some real Teflon. Plexiglass does not

like to do this.

 

Wow!  That looks so much better than mine.  Plexiglass can't stand the heat from solder gun, I think.  I use bakelite though.  Teflon is nice, but will it grip to the pins well?

Me thinks a diy 4070 I've got a pair of spare 404 drivers. Is it possible to replicate the housing design with a wooden cup?