Stax SR-X9000 review

[spritzer]

I’m going to post this in its own thread as so many people are asking me for X9000 impressions, and it makes sense to have them somewhere where they are easy to find.  I was also going to take some pictures to add to this review but I’m just wiped.  Might add some later if these ever present storms let up for some good light.  

I’ve now had the SR-X9000 here for over a week so time for a writeup... as my email inbox is full of people asking for just that. 🙂   First impressions were very promising, the build quality is superb, and those drivers are just a marvel to behold.  I do like the new replaceable cables even, though it is a bit of a copy of the King Sound setup, and they really should include a 2.5m cable and a 5m one, the 1.5m makes no sense to me.  The earpads might be a tad too big in terms of open area for their own good but they are well made and comfy.  That new arc design is also excellent, far better than the 009 mess.  The inspiration from the SR-Omega is clear but the build quality here is far, far better.  Same loose feeling fit too; they mostly just hang off the head with minimal clamping.  I really like how they drew inspiration from them, but I also have some issues with how that was executed… more about that later.  The system I’ve been using them in is my main rig, Denafrips Terminator DAC feeding a Carbon CC all being fed from my main PC. 

Now for the sound, these are clearly voiced in the same direction as the 009/009S but not as horribly colored as those two.  They sound open and lively with decent bass and the forward slant is there but far better than the predecessors.  I remember thinking… “these are what the 009’s should have been 11 years ago” so yeah, not bad at all.  For some recordings they really work but yeah… a few tracks in and the cracks began to show. 

A bit of a backstory, I’ve likened buying Stax to being in an “abusive relationship” for the last 15 years.  Back in 2007 they brought us the 007Mk2’s with all of their issues.  Sure, they could be fixed easily enough with some blutac but yeah it was a sign of things to come.  At CanJam it was confirmed there was a new version of the 007Mk2’s out and they were even worse (the Mk2.5 as we called them), the blutac helped but could not fix the terrible voicing.

Then it was announced a new flagship was incoming and the SR-009 landed in 2011.  Now we all remember the clusterfuck that was, drivers failing left and right and forward sound with pitiful bass response… yeah, I’m not a fan.  One bright spark was in 2014 when I got a new set of 007Mk2’s and they had clearly been changed for the better.  The port finally kind of worked and the voicing was more like the Mk1’s.  Then we got the limited edition 009BK (2016?) which I found to be a small improvement over the 009 but still that same sound and finally the 009S is 2018.  Less said about them the better, quickest I’ve ever sold one of my flagship phones there… 

That brings us to the present and since the wait for the SR-X9000 was so long, I had time to bolster my collection to compare against them.  I got a used set of 009S just to make sure I didn’t like them (that was still the case), a Voce (not arrived yet due to some shipping snafu’s) and finally the one I really wanted, a SR-Omega with early 007 Mk1 drivers.  I had a set a decade or so ago and it’s really the only set of headphones I truly regret selling.  I also got my final set of Audeze CRBN’s to compare against the new kid on the block. 

I had a lot of fun doing so and after a few hours I gravitated to a direct A-B test of the SR-Omega/007 against the X9000.  Makes sense as they are a similar idea, put a more modern driver into that same basic housing design.  That did reveal the two main issues with the X9000’s, the bright edge to everything which is just borderline annoying and more distracting than anything.   Second are the imaging issues… 

First off, the brightness, with the 009’s they were really intolerable, and I’ve never been able to just sit down and enjoy a listening session with 009’s.  It’s not that bad here but it’s always present.  Some tracks it just blends in and becomes part of the sound while on others it stands out and takes away from the immersion.  What makes it worse is that there is no logic to which tracks have that edge to them, bright ones which I would expect to have it… well it just blends in while darker ones have it.  Must be a resonance issue as there is so little damping here. 

Now with the imaging, I think Stax made a mistake having the outside screen angled like that.  On the SR-Omega it is perfectly parallel with the drivers but on the X9K, it is maybe 3mm further out towards the front.  This or some part of the driver structure might be the culprit for the odd imaging.  Let me clarify, they throw a large soundstage but it’s very much a “three blob affair”.  Nothing wrong with that really but it’s the front imaging which sounds off for me.  It’s all a bit to distant and boxed in while not being as focused as the 007 soundstage.  When you pick up on it, it becomes very apparent and distracting. 

As comparison, let’s take the SR-Omega and SR-007Mk2.  The SR-Omega throws a wide soundstage but it’s all a bit loose and diffused.  Now the 007’s (all of them really) have a much tighter, more focused soundstage which also does something unique, there are layers to it.  With the SR-X9000 it’s more like the SR-Omega (which makes sense) but more localized to the three blobs and the middle one has that odd boxed in effect while being a bit distant. 

Now other than these two things, these are well made and high performing sets, but these two things annoy me enough for them to not make my top/best ever list.  The SR-007’s are more laid back and “darker” but also more neutral and truer to the original sound.  The SR-Omega/007 is a more fun and looser version of that sound but those slight deficiencies just make them a welcome change, doesn’t make them any less neutral.  They simply act as a bridge bringing those two sounds together, absolute purity of the 007 with the more warm and loose nature of the SR-Omega. 

I feel I should also talk a bit about the new kid on the block, the Audeze CRBN.  Now I’ve had a few of them here, prototype units to the final production version and it really is the antithesis of the SR-X9000 is terms of fit and sound.  The CRBN is snug as it hugs your head with thick and supple earpads.  The sound is far more damped so it is darker but still very open and expansive.  Now they aren’t perfect, they have that slight issue with the midrange presence due to the heavy damping, but it is minor overall.  They are really what the HE90 could have been back in the day, more diffused than the 007’s but with proper bass.  Nice way to tie back the 007's were always being compared to the HE90 back in the day. 

Lastly, how are they to drive.  Well… as one would expect with a driver this size, they need a lot of power to behave.  That brightness will quickly get out of control, especially at higher volume levels when the headphones don’t have enough power behind them.  I’ve only tried them on a couple of amps so far so I’ll need more time with that, but I’d say powerful and neutral amps will suit these just fine.  

Conclusion/TL; DR

These are good but not as good as they could have been.  They are too forward sounding though not as bad as the SR-009, 009BK or 009S.  I crave neutrality over everything else, the headphones should just present the sound with as little an impact on it as is possible.  If they fail to represent a part of the spectrum, that’s fine but if they add something… then I have a problem with it.  The brightness and imaging issue does disqualify them due to that, but I will keep them around, nonetheless.  With some material they work well and plus I’m in a collecting mood… 😉   I'll probably add to review later on as I spend some more time with them. 

Finally, I’m going to be a bit cynical and think Stax are doing this sound signature on purpose and not for the obvious reasons.  This is exactly the type of sound which grabs you on a quick audition or impresses the useless audio reviewers out there who don’t know any better.  Back in 2002 the 007’s got no love at all as they are the definition of “unimpressive at first audition”, let along not many amps around at that time which could drive them.  Stax are clearly now trying to make money and not audio purist just trying to make the best product possible, nothing wrong with that, so I’m glad this wasn’t a complete hack job like the 009S. 

[Covered_Ears]

Many thanks for the review! I learned I'm hardly in a minority of people waiting for this. And I definitely hear you about how you characterize buying STAX; to me it seems like neutrality isn't a priority for them, which is a bummer for me as it is for me.

 

[TammerDown]

Damping mod time? 

[Kung]

I got the X9000 for about a month, and I also feel that the imaging of the X9 in the depth direction is a bit different from other stax headphones. The area near the middle is more concentrated and the rest is more diffused.I've tried a similar outside baffle with a deflection angle on my DIY estats，which has a little effect on the sound, but not what it sounds like on the X9.

[TammerDown]

1 hour ago, Kung said:

I got the X9000 for about a month, and I also feel that the imaging of the X9 in the depth direction is a bit different from other stax headphones. The area near the middle is more concentrated and the rest is more diffused.I've tried a similar outside baffle with a deflection angle on my DIY estats，which has a little effect on the sound, but not what it sounds like on the X9.

What's your view on them overall?

[Covered_Ears]

1 hour ago, Juansan2 said:

So I’m guessing we should wait for the “S” version in 3 or 4 years to solve the imaging problem……😜. 
 

It'll be what the 009S was to the 009, but with a bigger price differential! What a steal 🤣

[TammerDown]

holding out for the  LTDSRX9000BKS

[Torpedo]

We would be very thankful if the occasional visitors and review readers refrained their enthusiasm and need to post void messages. This is not Twitter.

[Juansan2]

The thing is that for many people (myself included) that grew up in the period where Stax products really represented the pinnacle of what headphones could do and were known for their transparency and neutrality it feels like such a let down that they have succumbed to colouring the sound signature to “wow” buyers. There are plenty of brands that have been pushing a signature “darker” sound with great success so it really feels like a sell out that Stax have taken the opposite route. 

[Pars]

3 hours ago, Torpedo said:

We would be very thankful if the occasional visitors and review readers refrained their enthusiasm and need to post void messages. This is not Twitter.

Or head-fi. We like to keep the signal to noise ratio high here...

[Pirx]

I had X9k over the week at home - my wife and kids decided it is not better than 009 and 007 mk1.

The lack of impact and energy in bass region  was the problem for them, not imaging.
Personaly I liked them, but didn't feel like this is my cup of tea.

In my opinion they are very different to 009, are little closer to my Omega with 007Mk1 drivers.

Would be nice to have them in collection and try them with different amplifiers, but after all I abandoned that idea.

[Catrace]

 

Hi All, sorry to be new in this forum and I do not want to enhance the noise floor and reduce the signal-to-noise ratio (SNR), here!

But with my "noise" I want to oppose a bit other “newcomers” here who are seeing only negative arguments against the X9k and I try to counterpart their "con noise" a bit by some more optimistic "pro noise" ;-).

And although being new here at the forum, I’m not new in headphones in general, so being quite experienced I think, hopefully not contributing pink noise, only, here.

I fully respect Spritzer's review and also his opinion and conclusion. Because it is a thorough review giving valuable insights into the pros and cons of the X9k from his point-of-view.

I also want to thank Spritzer for serving the community with thorough insights and an excellent review. That's great and many headphone fans have waited for his expert's review. Thanks a lot!

I want to contribute a positive signal on Stax SR-X9k.

And I must admit that I adore the new X9k.  I thoroughly compared it to my SR009 (yes, I have to admit that I like the tonality and signature of the SR009 from 2011. But I also adore the dark timbre of the SR007Mk1, so both are great for me. Quite different but great).

And when I compared it to my SR009, I must say that the X9k is a full level above. An incredible achievement, imho.

It is more detailed than SR009 with respect to frequency, timing (transients) and spatial resolution.

But even if it sounds contradictory, while being so ultra-precise it is extremely pleasant, fresh and ethereal, airy. Thus it never jangles my nerves. And it is NOT “bright in that sense” (what many people dislike with some Stax headphones). Yes, it is not dark like a SR007Mk1 but the "brightness" of the X9k is not bright in a negative sense, it is more “transparent” and airy than “bright” (not bright, not at all sibilant but very pleasantly transparent, I would call it).

And from my personal feeling (imho!) the space is great, too, well-spanned and very precise (accurately resolved). I cannot agree with the critical arguments on spatial properties by Spritzer. So, personally I did not detect them, so would not confirm. But of course, that's only me, maybe I just did not hear this issue.

I believe that finally (2011 came the SR-009. And the SR-009 was no real step up. A bit differently tuned but not really stepping up), the X9k really raises the bar in the headphone scene, not only related to Stax but also to the competing headphones, i.e., planars like Susvara, TC or whatever. So, time will tell, how the X9k will be anticipated in future. Maybe it becomes a new legend. Or maybe not. I personally see great chances for that :-).

[zolkis]

FWIW the X9K are my new favorite Stax overall, if price was not a factor (it is).

The comments about the 3-blob and slightly diffuse soundstage and perhaps too much leading edge are ringing a bell and likely founded (not really bothering me, though). It's not a reference neutral presentation perhaps, but it's close, and it's very pleasant with their relaxed dynamics and harmonic richness in that big head space. Some people I know tell me they love it, some others don't as much (preferring the SR-Omega or bits and pieces from others). I thought everyone would love the X9K, but no such thing yet.

To my aging ears they are not as bothering as the comparatively thin and lifeless sound of the 009/S and I like them better than the HE90 (not if I'd buy one anytime soon, as it's EV price range). For me, the X9K are completely enjoyable with my preferred genres (acoustic, jazz, small chamber, orchestra, pop, rock, indie etc), more so than the 007 Mk1 or Mk2 or Lambdas/Gamma with any mods,  though not the best price/performance ratio. That still has to go to my Libratum V3 and V5 (by far), which both are very close, better in some aspects (body, mids, bass impact at different frequency, focus, treble perhaps more organic) and slightly behind in others (efficiency, build quality, soundstage height, clarity/resolution, overall presentation), though YMMV and it's also genre and source/upstream dependent. (It's pity I haven't heard about Dima in a good while - no idea what happened, if you know something, Spritzer, please tell, but I have to assume Phenomenon is out, unfortunately, so you can consider the references to the Libratum irrelevant). 

I have yet to hear the CRBN, but based on what I read and hear around, might be so different, that they're catering to different preferences, and likely not mine. Will see, but likely I will wait for their next version.

Edited February 24, 2022 by zolkis

[spritzer]

Last I heard Phenomenon is gone, website and all. 

[justin]

Quote

 they really should include a 2.5m cable and a 5m one, the 1.5m makes no sense to me.

1.5m cable made for Japan, not viking

[spritzer]

True... 

I did order a L500 Mk2 to I can swap the cable out for the older all copper one to see if that makes any difference.  It won't but hey... any excuse to buy more headphones... 

[Oneguy]

@spritzerhow did the x9K sound after the L500 cable was swapped?

Count me in the weirdo camp that really likes the L700, 009s and x9000 sound.

[spritzer]

No real change and I just put them away as I got new toys.  I did give them another chance and yeah.. I'm never going to use these, it is unforgivable for me that they can't play all music without sound off, some songs are just not right.  They are just placed in my reference collection now and... yeah I'm not happy about this.  Hell I'd take the L500Mk2 over them... 

[Oneguy]

Ouch tell me how you really feel, lol. I’ve never bothered to listen to the L500mk2 but I did not care for the L500mk1 at all. Sound and worst of all the fit. Pads felt cheap and ears were touching the liner.
 

 

[spritzer]

The L500Mk2's are excellent and probably the best new Stax on offer aside from the 007's (which are hardly new at this point).  Far more balanced than they used to be and easy enough to fit L700 earpads if that is your thing

[Oneguy]

Thanks for the tip. I’ll head up to Tokyo this month and give them a listen.

[Aspirant Audiophile]

3 hours ago, spritzer said:

The L500Mk2's are excellent and probably the best new Stax on offer aside from the 007's (which are hardly new at this point).  Far more balanced than they used to be and easy enough to fit L700 earpads if that is your thing

I loved the L500MK2s but didn't trust my ears because they were the second set of Stax I'd ever heard. Four weeks, continued mistrust, and ten trades with the hifi shop later, I wound up getting the x9000s.

Fucking hell.

Considering getting the L500s for a point of comparison.

[Four Kneez]

What makes the L500Mk2 preferable to the L700Mk2? I heard the L700s at a show and enjoyed them quite a bit, but I haven’t had a chance to hear the L500s yet.

[spritzer]

They are a bit more relaxed sounding and neutral to me.  It's not a huge difference but the L500Mk2 gave a wow feeling for the first time in a long while when I first put them on.  I just got them for the bloody cable...  😉

[nopants]

My pair just came in, I'll try to keep an open mind comparing it to the 007