[Pale Rider]

 
Let us know the comparison between both when you get it in. Always interested in hearing the impressions between the 007 versions.

Sure thing. I definitely like the Mk1 better than the Mk2 I picked up from Price Japan. I like the 2, but to my ears, it sounds more characteristic of the 009 signature, and well, I already have one of those. 

 

[3X0]

There were three that went for a little more than $3k on yahoo.japan just this last year. And original T2 #33 for similar money.

I think they were broken or had other issues. I remember the Japanese->English translations included the word "junk" which isn't very promising.
 
Considering the SR-009 still goes for beyond $3k these days I'd certainly think the Omega to be worth considerably more.

 

[zolkis]

 Always interested in hearing the impressions between the 007 versions.

 
I've recently heard a SZ3-2xxx Mk2.5 vs a 703xx Mk1. Sounds quite different, more than I originally thought, with more bass slam, a bit darker and with somewhat coarser treble. The difference may be due to different springs and ear pads (deeper with the Mk2.5).
 
The Mk1 is more balanced and more linear (though still dark), feels smoother and more flat. It's indeed closer to the SR-Ω.
 
I assembled the Mk2.5 ear pads on the Mk1 and that did bring the sound closer to the Mk2.5 (more bass), but it still remained more balanced and more open sounding in character. 
 
However, with some music types where bass is welcome I actually preferred the Mk2.5. Each to their own... My ear pad mods do make the sound more open, so I wonder if the Mk2.5 would make a better subject for mods when it comes to bass -But I also like the treble and mids of the Mk1 more.
 
I became a bit tired of all the 007 controversy (different sound signatures between versions, mods needed to open up the sound etc). I also wish Stax could do a remake of the SR-Ω.
 
At least give me an SR-Ω frame (the best Stax frame IMHO) to put my 007 Mk1 driver in . Has anyone noticed defect SR-Ω's for sale, or ones that have been repaired (by default with 007 Mk1 drivers)?

 

[Tinkerer]

  I think they were broken or had other issues. I remember the Japanese->English translations included the word "junk" which isn't very promising.
 

 
That's basically the seller lingo for "untested" on yahoo.japan. You see it on headphones without amps to test and vise versa all the time. I remember two of them were pretty worn looking but nothing looked busted. The real gamble would be whether they had Mk I drivers instead. No way of knowing that with the pics that were up at the time.

 

[Tinkerer]

   
I've recently heard a SZ3-2xxx Mk2.5 vs a 703xx Mk1. Sounds quite different, more than I originally thought, with more bass slam, a bit darker and with somewhat coarser treble. The difference may be due to different springs and ear pads (deeper with the Mk2.5).

 
Was this the new ones you just got from Price Japan? And do you have the physical measurement difference between the old 70xxx brown pads and the ep-007's?

 

[JimL11]

Is there correlation data between total odd harmonic distortion and subjective sound quality of amps?

Also, there is an opinion that tube amps tend to have mostly even harmonic distortion, and most transistor amps have mostly odd harmonic distortion, but I wonder what actual data we have on this, and also on the correlation with subjective SQ.

There have been a number of suggested ways to modify total harmonic distortion numbers to make them more consistent with subjective results.  For example, odd harmonics seem to be less tolerable, higher order harmonics seem to be more audible and less tolerable, intermodulation distortion seems to be less tolerable, etc, and there have been suggested remedies to try to weight the upper harmonics more heavily to try to adjust for this.  However none of these suggestions have achieved consensus recommendation, so we are stuck with THD.  Not the best state of affairs but there you are.

 

[nemomec]

 

 Always interested in hearing the impressions between the 007 versions.

 
 
The Mk1 is more balanced and more linear (though still dark), feels smoother and more flat. It's indeed closer to the SR-Ω.
 

 
Yes this is also my experience, the first versions of SR-007 MK1 up to SN 705xxx sounds closer to the original SR-Omega. The newer versions are slower and darker and not so balanced. The SR-009 is objectively seen the better SR-Omega and i think it was developed with the SR-Omega technologie but with a smaller diagram for lower distortion. On the other side the SR-Omega has more mid bass and a little bit more colouration that many people like. In the end its a decision of taste between the "ultra transparent and clear" SR-009 and the "powerfull high resolution" SR-Omega or the similar SR-007 MK1 first series.

 

[Blackmore]

The only way to stimulate Stax of getting the idea of remaking of original Omega is by writing them, however, you cant do this by e-mail anymore, only by writing an letter, but I dont see this happening.
Personally, I have tried O2 many times, black color, thats all I know about their version, but to me they are darkish and I GUESS require something more powerfull to drive them than SRM 600LE, but even then, I have no idea if I really going to like them after all and 009 are simply speaker system price range up here.
 
 
We abolished E-mail address "info@stax.co.jp", printed in a brochure.
If you have any questions, please contact a distributor of the country where you get easy access.

 

[Tinkerer]

   
Yes this is also my experience, the first versions of SR-007 MK1 up to SN 705xxx sounds closer to the original SR-Omega. The newer versions are slower and darker and not so balanced. The SR-009 is objectively seen the better SR-Omega and i think it was developed with the SR-Omega technologie but with a smaller diagram for lower distortion. On the other side the SR-Omega has more mid bass and a little bit more colouration that many people like. In the end its a decision of taste between the "ultra transparent and clear" SR-009 and the "powerfull high resolution" SR-Omega or the similar SR-007 MK1 first series.

 
Just thought I'd add that Mk I Early types extend to at least SN707xx. Actually, wasn't the change to SZ1 the turnover to MK I Late?

 

[zolkis]

 
Just thought I'd add that Mk I Early types extend to at least SN707xx. Actually, wasn't the change to SZ1 the turnover to MK I Late?

 
That is hard to tell - only by listening I guess. Putting together info from 2 people (padam and spritzer), the first batch of Mk1 came with the old style carbon-fiber imitation box. Then there was a later batch that came in the new style box, but we don't know for sure where the "late" 7xxxx Mk1 batch started (it could be told only by listening) so the box stuff is likely speculation. Perhaps some materials sourcing has changed over time, they always do, pads especially, perhaps even diaphragm material (of the same spec but different make) but I don't think that correlates with the boxes.
 guess when Stax really made a change, it was reflected in the serial numbers: SZ1, SZ2, then a bigger change happened with the SZ3. The person who has most experience with 007 versions is spritzer, ask him on the other side .

 

[zolkis]

 
Was this the new ones you just got from Price Japan? And do you have the physical measurement difference between the old 70xxx brown pads and the ep-007's?

 
The recent (one year old) Mk2.5 SZ3 that I heard in comparison to my own Mk1 was only a local audition.
The 007A order on amazon seemed to be stuck for a while, it got fishy and I have canceled it: I decided to buy an already known and tested second hand piece. I am not sure measurements will do justice to the differences I hear, but I will do them when I will have both kinds here for a prolonged testing.
 
I could measure the brown pads vs black pads on my 007, but it does not make much sense, you hear more differences than you can measure. Their seal, firmness, thickness is slightly different, and that comes through differently when you wear them vs when you use a measurement coupler. I only use measurements to rule out obvious flaws, but a trained ear can provide a lot of relevant information on top of measurements. Mine are not so well trained but at least experienced .

 

[nemomec]

   
Just thought I'd add that Mk I Early types extend to at least SN707xx. Actually, wasn't the change to SZ1 the turnover to MK I Late?

 
The newest SR-007 MK1 that i know and sounds like the first series for me was the SN: 705xx with carbon box, i haven´t seen and heard a 706xx or 707xxx. SN 71xxx sounds different like the SN SZ1-xxxx and comes with the new box. There are a scattering with the SN 71xxx and SZ1-xxx pieces, some sounds very slow and dark some closer to the first series. The SR-007 MK2 series with SZ2-xxxx sounds all same to me and darker/smoother like the most MK1 versions. The SR-007 MK2 with serial MK3-xxxx sounds to weak for me, much darker and not so balanced, but i haven´t heard the newest SR-007 MK2 version.

 

[Drumonron]

Just ordered a black STAX SRM-727II from headamp.com and Justin will be modifying it for me. 
Will be using this for my SR-007 and SR-009.  Thoughts?

 

[zolkis]

What mods? Including power supply (better caps etc)?
When I heard a 727 II it was perhaps not the best available, but good enough. The problem that I have seen is quite low quality parts in the power supply (rectifier, capacitors, etc). I guess an outboard PS would be better for the 727 since the case is too small for a good one.

 

[paradoxper]

Feedback mod.