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Stax SR-009S Electrostatic Headphone Review

Rate this headphone:

  • 1. Poor (headless panther)

    Votes: 49 20.7%
  • 2. Not terrible (postman panther)

    Votes: 62 26.2%
  • 3. Fine (happy panther)

    Votes: 78 32.9%
  • 4. Great (golfing panther)

    Votes: 48 20.3%

  • Total voters
    237
Interesting. I've been given a bit of a side-eye when talking about how wonderful my electrostat KSE1200s are here, esp. eq'ed (stock FR is even more terrible than this). That they're electrostats should have no bearing as the distortion level difference shouldn't be in the realm of audibility. Yet as much as I try to get on board with that notion objectively, every time I put them on there is this wicked sense clarity that is hard to put into words.

Unfortunately I have these in storage while I'm doing a European trip but may send these off for eval later this year. @Amir, you'd be surprised to find these go incredibly loud without clipping, even eq'ed with a decent bass shelf (they're an amp/earphone pairing, so driving them isn't an issue).
 
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Yeah good great very nice
But is it sensible to get one of these instead of a huge number of other (great) things?
Knock $3000 off from list price and I'll happily vote great. As it stands now, it deserves no more than "not terrible".
 
Yeah good great very nice
But is it sensible to get one of these instead of a huge number of other (great) things?
Knock $3000 off from list price and I'll happily vote great. As it stands now, it deserves no more than "not terrible".

It's hard spending $$ on a flawed product. That said comparing against other 'great' things, can it do something those can't? The FR sucks but it can be (mostly) fixed. Bass is tricky. It's the bane of most stats. You can't just elicit rock bottom distortion out of another otherwise great product.

FWIW, you can pick up a KSE1200 system (electrostat earbuds) for about $1200-1300 used. They need even more significant tweaks to the FR but given EQ they're sublime and an excellent value if you want to play in this realm.
 
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100dB peak SPL in the low bass in music is far from insane levels.
It is about 75phon (we hear in phon's not dB). This could be the case when such heroic EQ is applied and one wants to play at comfortably loud levels.
The major drawback of electrostatic headphones is maximum SPL.

This is why testing headphones at 114dB is not as crazy as some think.
Peak SPL is something very different from average dBA noise levels.

This headphone should be able of 103dBSPL @ 20Hz. That’s miles beyond any bookshelf out there. Even the beefy ones.

That’s an insane number that I personally only experience in concerts and festivals.

I’m under the impression that the distortion is so vanishingly low that that excursion wall hits pretty hard and when you experience it as a reviewer it’s dishonest not to report it
 
So the "speed" and sense of resolution of electros have been confirmed by the most die hard objectivist. Now a review of the DCA electro would be a fun comparison
 
Heard it a while back. Thought it sounded boring but has its strengths (texture, imaging and detail). My audio friends all praised the X9000 and urged me to give it a listen instead- unfortunately I never had a chance to :')
 
Hate to say it, I voted poor.
@this price it has to excell beyond measure and superlative directly out of the box to justify the cost @ $4545. That price has swagger and it simply must be superb or I find it insulting.

Yes, cool that eq fixes much of it. So drop the 1st 4, charge $545 and we are mostly good.

By the way why $4545? Strange price.

Interesting review. Thank you.
I tend to agree- for $4K+ you shouldn't get a 'mixed bag' product that does a few things very well and quite a few not well at all. Looks like the Dan Clark Stealth or Expense (excuse me, 'Expanse') 'walks the walk' better at the price, I have heard what I think was the original 009 at a show and thought it sounded OK. It seems like planar drivers of all types are 'one trick ponies' to a certain extent, The $4545 might be the conversion of the price in JPY.
 
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@amirm If you liked EST sound, maybe its time to ask DCA for a Corina sample to review? apparently it has proper tuning and it is one of the few ESTs that can do bass (alongside Audeze CRBN)

Are there measurements of the Corina out there? I'm coming up empty. Curious to see how good of a FR Dan was able to achieve.
 
Are there measurements of the Corina out there? I'm coming up empty. Curious to see how good of a FR Dan was able to achieve.
DCA Corina FR.png
 
I have always felt that strict adherence to any equalization curve at frequency extremes was silly - it is only applicable at a particular, fixed, volume. I do not know the volume for which the Harman curve is appropriate. At a louder level, the low frequency response of this pair of headphones might be just perfect, and no additional boost would be necessary, and could even be wrong to apply it. Certainly, at quieter listening levels, boosts at the frequency extremes would be desirable - but there would be no hitting of a loudness capability wall. As often as I hear that low distortion is a poor correlate of percieved sound "quality" (I have no opinion on that subject) I have never heard speakers (I have limited experience with headphones) which I liked, that did not have low distortion. For me it may not be a sufficient, but it is a necessary quality in a pair of speakers. I suspect that it might apply to headphones too.
 
With the ability to afford aspirational audio should come some understanding of the value as well. Exceeding certain price points for any category the ROI starts to go over a cliff. This one for me fits that example.
 
Hate to say it, I voted poor.
@this price it has to excell beyond measure and superlative directly out of the box to justify the cost @ $4545. That price has swagger and it simply must be superb or I find it insulting.

Yes, cool that eq fixes much of it. So drop the 1st 4, charge $545 and we are mostly good.

By the way why $4545? Strange price.

Interesting review. Thank you.
Completely agree!
 
This headphone should be able of 103dBSPL @ 20Hz. That’s miles beyond any bookshelf out there. Even the beefy ones.

That’s an insane number that I personally only experience in concerts and festivals.

I’m under the impression that the distortion is so vanishingly low that that excursion wall hits pretty hard and when you experience it as a reviewer it’s dishonest not to report it

Amir said this:
I wished for a bit more bass but I could not get it. Volume would go up to medium loud after which I would hear static.

That mirrors my experience, the data in the review and the reports of many owners.

Not suited for bass heads and cannot be driven to impressively loud levels. That said it certainly has some nice aspects (effortless sound) but agree with most others that heard some Stax models... the SR007 is the 'better' one.

I don't own any Stax headphones mainly because of the price, the cheap, creaky plastic construction (of the 'cheaper' models), lack of 'body' in the bass and the need for energizers. They do have some really nice properties and those that like those properties, don't play loud and have money to spend in abundance I do get the appeal of this (electrostatic).
 
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Please somebody educate me, so this headphone had good performance in distortion levels which I thought means friendly for EQ; but “shelving filter caused severe distortion at anything but moderate levels” so now I’m confused
 
What a curious headphone, I'm not sure what to think about this one. I don't know why the distortion was so low yet it wasn't possible to EQ up the bass, because 110dB distortion line was good, so should be ok when adding around 5dB to the bass with EQ (albeit not if you want to listen to loud enough listening levels to deafen you during extended listening). The stock frequency response doesn't look too great, somewhat fixable with EQ judging by the measurement. A very glowing subjective review though. Well I'm on the fence & confused about this headphone, and it is very expensive too, I'd choose some other options, guess I'll vote it ok'ish.
 
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What a curious headphone, I'm not sure what to think about this one. I don't know why the distortion was so low yet it wasn't possible to EQ up the bass, because 110dB distortion line was good, so should be ok when adding around 5dB to the bass with EQ (albeit not if you want to listen to loud enough listening levels to deafen you during extended listening). The stock frequency response doesn't look too great, somewhat fixable with EQ judging by the measurement. A very glowing subjective review though. Well I'm on the fence & confused about this headphone, and it is very expensive too, I'd choose some other options, guess I'll vote if ok'ish.
My vote is "not terrible" considering one might buy this cheaper than the Stax:
and spend the rest for a very decent HPA. And, last but not least, not having to bother with EQ as a "bonus".
 
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