[mulveling]

Awesome pics! Indeed, the Stax factory is serious business. And lol at 009 being the only one worthy of dust covers.

 

[purk]

  Awesome pics! Indeed, the Stax factory is serious business. And lol at 009 being the only one worthy of dust covers.

Channel imbalance sir!

 

[chinsettawong]

One of the guys in the pictures is coating the diaphragm.

 

[zolkis]

Yes, and I wonder what do they use nowadays: Mylar or PEEK, and what coating material.
Edit: and if PEEK, which type: carbon fiber reinforced, or the latter + graphite lubricants.

 

[duesentrieb]

Hi folks, when reading your posts, I thought it might be appropriate to step into the discussion here with a more technical theme regarding Stax small signal & power bandwidths...
 
Some general remarks
Recently I acquired a SRM-353x / SR L700 combo, playing very nicely, while hooked up to a T+A R preamp via homemade unbalanced Cinch Line-Out to balanced XLR (to avoid ground loop hum). Sonically I agree with what was stated here before, only very little nasal character of the L700, but I like the rectangular can better and really appreciate the flat bass response (flat as far as I could measure it properly with a 1/4'' mic-capsule and cardboard adaptor...).
Anyway, when attaching a 2.5m extension cable, I was curious about the potential influence due to increased capacitance.
Well I heard no difference, fortunately, but took some measurements.

The SRE-725 cable seems to add some 60pF differential capacitance between the R+/L+ and R-/L- terminals. There is more capacitance, especially to the Bias wires, around 100pF. Considering a symmetrical electrical model with constant membrane voltage,  app. 89KHz small signal bandwidth may be expected by calculation (interestingly acc. to Stax in their specs) and respectively 53KHz including the extension cable, which is perfectly Ok.
When peeking into the 353X amp, it looks that the basic circuitry is similar to the 323s, which was discussed here before (less Leds illuminating the scene though).
From the power consumption of 22W though one could estimate some 5mA of sink current in each of the 4 class A amps´ current sources,
which reduces the estimated power bandwidth @400Vrms from some 22KHz to just 14KHz, according to my calculation...of course at lower levels higher again, to avoid any misunderstanding and misleading discussion upfront...
 
My Qs and for further discussion (comments welcome!):
 
- Did anybody hear differences with the extension cable, especially when playing loud?
- Did anybody measure those amp sink currents???
- Is there a schematic available for the SRM-353X?

 

[Pokemonn]

I have a extension cable(expensive 2.5m one). I heard it very very slightly harsh/grainy when hooked up to 009/007t. but it maybe placebo effect

 

[GU1DO]

   
The L700 has good deep bass, sound stage is big. It still has the "Lambda coloration" in the mids (slight nasal coloration/hardness in the upper mids, but only evident when compared to the 007 or 009).
The 007 Mk2 (SZ3 series) is the same as the  007A apart from the color. They have better bass slam, better mids, more correct tones, and overall better sound than L700. Sound stage is huge. 
The 007 Mk1 early series (hard to find) have less bass slam than 007 Mk2 SZ3, but somewhat better bass extension. Mids are more pronounced (and the 009 mids are even more pronounced). Sound stage is a bit narrower than 007 Mk2, but also depends on the headband setting. You need to personalize the 007 headband. I pressed in the middle of the headband (making it more straight) and increased the lateral angle inwards so that pressure is even on my head, but ever slightly more on the lower part (I wear glasses).
A few pages back I posted some 007 measurements.
 
I recommend you listen to the L700, and the 007 Mk2 or 007A SZ3 series.
 
With time, you might still end up with a (used) 009, even though you say you can't afford it now .

 
 

  I don't think that is correct. I had an SZ3 black 007 UK model about 2012 model and it sounded bad. I now have the 007A 2015 model which I got from PJ and it sounds really damb good. Tight bass, more detail, faster. The current 007 black is also supped to be the same as the 007A I have, though not heard it so can't say. I have compared my 007A to a good example 007 MK1 and they are closer than different. If anything I prefer the 007A as the treble is livelier.

 
 

   
I don't think Stax makes two distinct 007 drivers. Others in this forum also suggested the current 007A made for Japanese market is the same as the black 007 Mk2. My 007 Mk2 was made in 2015. I have heard another made in 2015 and they sounded the same. Also, based on your subjective descriptions of the sound of your 007A in this forum, I am pretty sure the current Mk2 is the same.
But if you would go to a Stax dealer you could be in position to compare your 007A with a recent Mk2. 

 
 
Really i am thankful for all the input guys ,, it was very helpful 
 
i just listed my 2170 in ebay . really i cant stand the lack of bass and sound stage
now searching for new much better and expensive model
 
Thanks again .

 

[arnaud]

- Did anybody measure those amp sink currents???

 
There you go: http://www.head-fi.org/t/582518/electrostatic-amplifiers-voltage-ratings#post_7925458

 

[wuwhere]

KGSSHV Carbon current output rating (post #158) http://www.head-fi.org/t/766237/kgsshv-carbon-hows-it-sound-with-the-009s/150

 

[duesentrieb]

  KGSSHV Carbon current output rating (post #158) http://www.head-fi.org/t/766237/kgsshv-carbon-hows-it-sound-with-the-009s/150

 
 

   
There you go: http://www.head-fi.org/t/582518/electrostatic-amplifiers-voltage-ratings#post_7925458

Thanks guys,
 
sorry for not finding this myself.
I think it would be helpful to move the discussion to the other thread (electrostatic-amplifiers-voltage-ratings#post_7925458), this deserves some new acitvity anyway...can someone do that for me?
 
Btw.:
Need to go deeper into the capacitance matrix of the L700 for a better understanding what the situation is and how much sink current is really needed.
From my understanding the quoted 110pf are between both stators plus the cable. Since this capacitance is driven differentially, it will count double in the slew-rate or power bandwidth calculations...or in other words the stator and cable charge voltage completely reverses, e.g. meaning going from +565V to -565V @ 5mA of sink current (in this case), which corresponds to a slew-rate of 45V/us in total or 22.5V/us in one amp branch. On the other hand, if one considers the bias lead voltage as constant (there are good reasons) and just look at the measured capacitances from Bias to L+/L-/R+/R- in the range of 140 to 160pF and single-sided voltage swing, some 33V/us result.
In real world the scenario gets more complicated since the adjacent R-/L- leads will be out of phase regularly and additionally load these amp branches capacitance-wise...plus the extension cable load...
 
Anyway, an experiment resulted relaxing. Listening to very loud L/R-uncorrelated white noise with no extension cable in between and then plugging the extension cable into the second 353x output yielded no audible difference...this is it for the moment.

 

[astrostar59]

   
 

Thanks guys,
 
sorry for not finding this myself.
I think it would be helpful to move the discussion to the other thread (electrostatic-amplifiers-voltage-ratings#post_7925458), this deserves some new acitvity anyway...can someone do that for me?
 
Btw.:
Need to go deeper into the capacitance matrix of the L700 for a better understanding what the situation is and how much sink current is really needed.
From my understanding the quoted 110pf are between both stators plus the cable. Since this capacitance is driven differentially, it will count double in the slew-rate or power bandwidth calculations...or in other words the stator and cable charge voltage completely reverses, e.g. meaning going from +565V to -565V @ 5mA of sink current (in this case), which corresponds to a slew-rate of 45V/us in total or 22.5V/us in one amp branch. On the other hand, if one considers the bias lead voltage as constant (there are good reasons) and just look at the measured capacitances from Bias to L+/L-/R+/R- in the range of 140 to 160pF and single-sided voltage swing, some 33V/us result.
In real world the scenario gets more complicated since the adjacent R-/L- leads will be out of phase regularly and additionally load these amp branches capacitance-wise...plus the extension cable load...
 
Anyway, an experiment resulted relaxing. Listening to very loud L/R-uncorrelated white noise with no extension cable in between and then plugging the extension cable into the second 353x output yielded no audible difference...this is it for the moment.

Short story, the more power, the better the power supply and the better the design of an electrostatic amp, the better the sound. I wouldn't get hung up on all the stuff above.
 
But IMO all the KG amps I have heard are better than any current Stax amp, and it goes something like Stax (any model) - KGSS, KGST, KGSShv on board, KGSShv off-board (Sanyo or IXYS) KGSShv Carbon - BHSE - T2. That seems to be the norm for most who have heard all those at one time. I have heard some Stax amps, had the KGShv Sanyo off-board, have the Carbon now and heard the BHSE many times. AIMO.

 

[MrOTL]

I am big fan of Stax headphones!!
cause.. gotta big head lol....

 

[zolkis]

I had the chance to compare my modded 007 Mk1 with Thinker's SR-Ω and Lambda Sig driven by the Aristaeus.
 
Short version: the Omega is the most perfect sounding headphone I can imagine. The Orpheus didn't make that same impression, nor the 009.
 
The construction is also among the best, perhaps except the headband is a bit large for me even at the tightest setting .
It has the best designed ear pads I've ever seen (and similar to the principles HD800 pads are using). All I learned in the past years about ear pads are already incorporated in the SR-Ω pads. I wonder why Stax didn't stick with that... I am contemplating to clone them as I believe it would improve the younger Omegas (007 Mk1, Mk2/A, 009) as well.
 
For reference, earlier I posted the FR measurement of my 007 Mk1 with modded earpads.
http://www.head-fi.org/t/677809/the-stax-thread-iii/10335#post_12952833
 
Compared to the SR-Ω, it still sounded more closed with less treble and narrower sound stage. So I made 2 small mods right there, adjusted the head bands to match the pressure of the SR-Ω, and took out the dust screen which seemed to be denser woven fabric than the one used on the SR-Ω.
 
After these mods they sounded very close actually, and it took multiple tracks to realize what were the differences:
- the SR-Ω has more treble, yet without sounding bright (the 009 has even more treble)
- but they have similar musical resolution, i.e. things are not masked on the 007 Mk1
- the 007 Mk1 sounded a tiny bit clearer in the mids, the SR-Ω sounded cleaner and clearer in the upper mids and treble
- bass extension, impact and texture is similar
- judged by ear, the SR-Ω is even more linear (maybe has more treble spikes), although the modded 007 Mk1 is pretty good, too
- the SR-Ω sound stage is slightly bigger, about similar size as the 007 Mk2/A, but adjusting the headband on the 007 Mk1 brought that close.
 
The SR-Ω is the better phone, especially that it didn't have any mods, but behold, there are settings for the 007 Mk1 that get it really close to the SR-Ω and it costs much less, but takes a lot of tinkering.
 
We both agreed that in the tested setting the modded 007 Mk1 was better than the 009, and the SR-Ω  surely is.
 
My next mod for the 007 Mk1 is SR-Ω ear pads cloning and new dust screen. It may also elevate the 009 to new heights. Will keep you updated.
 
A few words about the Lambda Sig that was there. This particular unit sounded amazing even when compared to the SR-Omega and the 007 Mk1. Very clean and clear in the mids and highs, with no Lambda-sibilance or brightness or hardness (that is the first Lambda I haven't heard that, maybe because the amp? or is it *that* good?). At least it has the Sigma drivers which is good start. There is very good bass too, albeit not at the level of the Omegas (say 80%). One gets 90-95% of the overall sound quality of the big brothers and no compromise in the mids+highs. I don't remember hearing a better Lambda, Lambda Sigs and x07 and L700 included. I remember a 404LE making very good impression too, but fresh out of the Omega I was surprised how good this Lambda Sig was and I'd say better than the LE. 
 
OT. There is a fake SR-Ω sales ad out there in German sites these days. The pictures looked real, with a plausible serial number. After contact the guy responded with a text written with kind of bad German which didn't match well with the claimed location, didn't address my questions, and on a google search I've seen others discussing the same email. Scam probability close to 1. By all means be cautious when buying SR-Ω: fake deals, fake drivers, etc.

 

[musedesign]

Hi All,
  "Can you say overwhelmed ?"  696 Pages of Stax ? (In this section, two more previous sections).
 
Gently asking.  When I was a 17 year old kid (30+ years ago) listened to Stax (no idea of the model) earspeakers and was blown away.  To this day still remember the Stax earspeakers sound.
 
Can people recommend sub $500 Used Stax ?  Have looked online and confused by all of the models.
 
Thank you ! 

 

[AnakChan]

  Hi All,
  "Can you say overwhelmed ?"  696 Pages of Stax ? (In this section, two more previous sections).
 
Gently asking.  When I was a 17 year old kid (30+ years ago) listened to Stax (no idea of the model) earspeakers and was blown away.  To this day still remember the Stax earspeakers sound.
 
Can people recommend sub $500 Used Stax ?  Have looked online and confused by all of the models.
 
Thank you ! 

 
Difficult one. If you don't mind used, you may be able to look into the likes of the SR-404LE, but then you'll still need to have a little more $$ for the amp.