Stax SR-009 Electrostatic Earspeaker (Playback 54)

Best Headphone Ever

March 7th, 2012 -- by Chris Martens
Source: Playback

Finally, the SR-009 always seems able to dig deep (deeper than any other headphones can) to tease out the innermost elements of tonal purity and, yes, tonal beauty in any given recording. I was floored by both the breathtaking intricacy and coherency of the Stax ‘phones as they reproduced the Clockwise performance of Robert Paterson’s Freya’s Tears [American Modern Recordings]. Freya’s Tears is a short piece in three movements that was written for Clockwise, a duet consisting of a harp and violin. The middle movement of the piece, “Freya’s Tear” features soaring and at times very intricate harp passages set against beautiful yet at times quite angular and penetrating violin passages. I was struck by the fact that the SR-009’s were able to show the round, fast-paced, and percussive quality of the harp, complete with luscious tonalities that seemed almost illuminated from within, while at the same time perfectly capturing the knife-edge balance struck between sweetness and incisiveness as the violin explored lines written in its upper registers. The eerie thing is experiencing how rich, full, complete, and lavishly detailed the SR-009 can make two instruments sound, even when playing intricate material simultaneously. No other headphone I know of can match the SR-009 is this respect.

CONCLUSION

Consider this headphone if:

• You want a neutral, accurate sound with wide bandwidth, and you prize clarity and low distortion.

• You’re the sort of person who really wants to know precisely what’s going in his or her audio system and/or favorite recordings. The SR-009 will give you “the truth and nothing but the truth,” and will do so with disarming ease and grace.

• You believe, as does Mercedes-Benz, in a philosophy of “the best or nothing.” At this moment in time, we think the SR-009 is the finest headphone in the world. Period.

Look further if:

• Down deep, you think only a "nutball" would consider spending $5250 on a headphone. But caution: Once you hear the SR-009 in action, you may discover that you are, in fact, just such a "nutball."

• You find the overall cost of an SR-009 system daunting (recognizing that SR-009-based systems can easily set you back $10k or more, once you factor in the price of an appropriate amp). Also look further if you aren’t prepared to spend some time finding your ideal amplifier match.

Ratings (compared to cost-no-object headphones):

• Tonal Balance: 9.5 (some might discern a very slight region of emphasis in the upper midrange, though I am not convinced that this is anything other than the Stax “telling it like it is” regarding flaws commonly found in modern recordings).
• Clarity: 10
• Dynamics: 10
• Comfort/Fit: 9.5
• Sensitivity: 9
• Noise Isolation: 3 (Frankly, the SR-009’s do virtually nothing to block out external noise—perhaps the price we pay for their terrific transparency?)
• Value: 8 – 10 (Depends on your frame of reference. Yes, it’s the most expensive headphone on the planet, but no, $5250 is not too much to pay for the finest headphone there is—and one that puts many five- and even six-figure loudspeakers to shame.)

BOTTOM LINE:

Stax’s SR-009 is a reference headphone that sets a new benchmark for transparency, low distortion and dynamic accuracy while delivering a wide and balanced frequency response. This is the standard against which all other top-tier headphones must be compared.

SPECS & PRICING

Stax SR-009 Electrostatic Earspeaker
Driver: push-pull circular electrostatic element, diaphragm is less than 2 microns thick.
Housing: open-back, machined aluminum
Frequency Response: 5 Hz – 42 kHz
Required Bias Voltage: 580V
Sensitivity: 101 dB/ 100V
Ear Pads: handmade, Lambskin leather
Signal Cable: High-purity, “six nines” copper, sliver plated.
Weight: 21.3 oz.
Warranty: 1 year, parts and labor
Price: $5250

U.S. Distributor:
Yama’s Enterprises, Inc.
(310) 327-3913
www.staxusa.com

Comments

Gadgety -- Fri, 03/09/2012 - 04:34

So how do you account for this improvement that warrants a doubling of the price: thinner diaphragms and stiffer stators? I doubt that explains it all. What about the amplifier? Can Stax explain what the performance upgrades are, and how they warrant a doubling of the price?

Chris Martens -- Fri, 03/09/2012 - 14:09

Hi Gadgety:

You pose a fair question. I'll tell what I know based on my investigations thus far.

1) The differences are not solely attributable to the amp, good though the Woo Audio WES is. I know this because I have heard a pair of Stax SR-007 MkIIs alongside the SR-009s with both headphones driven by the very same WES amp. I found there was quite a big performance gap between the SR-007 MkII and the SR-009, and since the same amp was driving both 'phones at the same time, I have to think the difference was attributable to the superior design/execution of the SR-009.

2) I'm not sure whether you will find Stax's information on the SR-009 compelling or not, but to see the company's own explanation of the improvements made in the SR-009, follow this link: http://staxusa.com/Earspeaker/STAX-SR-009.html

3) Do the improvements warrant a doubling in price? Only you can answer that one.

As I mentioned in this review, today's best dynamic and planar magnetic 'phones can get you fairly close to the performance of the SR-009 for much less money (think of prices in the $1k - $2k range versus $5250 for the Stax). Still, in high-end audio (and the SR-009 is unquestionably at the high end of the high end), the final 5% or so of performance has traditionally been the hardest to achieve and also the most expensive. This is a roundabout way of saying that the value proposition of the SR-009 (and of the high performance amp it will require) is very much in the ear (and wallet) of the beholder.

Personally, I can't afford the SR-009 or the amp I would need to match with it. So, I content myself (quite happily) with a set of planar magnetic 'phones and a good but not painfully expensive amp. But that doesn't stop me from admiring what Stax and Woo have achieved, or from dreaming that one day I'll perhaps figure out a way...

Best, Chris Martens

Chris Martens
Editor, Avguide.com/Playback/The Perfect Vision

tonereef -- Thu, 03/15/2012 - 19:02

Chris, you mention what you feel to be a slight upper mid-range rise. In my experience these phones require careful matching of amps and/or sources for them to sound natural in the treble, at least if your system is really open up there. In my case it helped to substitute 6FQ7s for 2 of the 6DJ8s in my DIY tube amp. Quite a lot of people have commented that the 009s sound bright with different amps; of course, there is considerable variation in the perception of highs via headphones due to outer ear differences (not to mention HF hearing loss!). Tyll Hertsen's measurements (at Inner Fidelity) show a bump of about 3 dB around 1K. They also show that the bass below about 50 Hz is down 3-4 dB compared to the upper bass/mids. I believe I hear this and that it's not caused by the source or amp or cables; did you not hear it with the Woo? In any case these are wonderful phones, for all the reasons you mention.

Tony Reif

Chris Martens -- Fri, 03/16/2012 - 11:30

Hi tonereef,

You do raise a good point. The SR-009's are VERY sensitive to tubes or to any other elements of the system. The Stax 'phones can and do expose even the smallest system changes or tuning adjustments.

I experienced no brightness problems at all when the SR-009 was used with the Head Amp Blue Hawaii SE and the pre-production prototype of the Cavalli Liquid Lightning, and only occasional trace amounts of upper midrange brightness (on some but not most recordings) through the Woo WES. The tradeoff, however, was that the Woo--as configured with Sophia driver tubes and Shuguang 50 Years Treasures output tubes--was arguably the most transparent/open-sounding of the three amps. According to Jack Wu, you can temper those trace bits of midrange forwardness observed in the WES either by making a different tube choice or by ordering up the WES with the extra-cost V-CAP options that Woo offers.

In my experience, perceived bass output levels varied somewhat with different amps, too. I would say that in general terms the extreme low end of the SR-009 may not be **quite** as full-bodied as that of a properly driven Audeze LCD-3 or LCD-2, Rev.2, nor as rock solid as the bottom end of an also properly driven HiFiMAN HE-6. But with that said, I would add that the SR-009's low frequency balance often tends to seem more consistent with the sound of live music (most of the time, at any rate), and that its pitch definition and transient speed are spectacularly good. All in all, I could live happily with the SR-009's bass performance; it certainly didn't seem "bass shy" to me, and I'm normally quite sensitive to (or even finicky about) such things.

Chris Martens
Editor, Avguide.com/Playback/The Perfect Vision

dyl1dyl -- Fri, 03/23/2012 - 04:16

Hi Chris,

Would be very interesting to read a comparison piece between the 009s and the Audez'e LCD-3s. Any news on whether you guys have/are going to have a pair of the new Audez'e flagships in soon?

Best Regards

Speakers: B and W 802 Diamonds, Bose Lifestyle 35, Audioengine AP4 Bamboo
Headphones: Audeze LCD-3, LCD-2, Beyerdynamic T5p, dt880, AKG K701, Ultrasone HFI-780
IEMs/Earbuds: Westone 4, Mons

Chris Martens -- Fri, 06/22/2012 - 12:54

Hi dyl1dyl:

A review of the Audeze LCD-3 will be coming soon in Playback.

Best,

Chris Martens

Chris Martens
Editor, Avguide.com/Playback/The Perfect Vision

aross -- Thu, 08/30/2012 - 15:07

Chris: When I purchased the WES, Jack Wu suggested the ultimate tube upgrades and internal parts upgrades, I purchased both. Some time later, when the SR 009 was released, I purchased those as well. Before I come off sounding like a "big spender," let me mention that as a teenager in the 1950s I was designing and building my own audio equipment, and into the 1960s building "top rank" amp and preamp kits. A successful legal career enabled me to reach the ultimate audio heights in the 1980s. In the early 1990s, as empty nesters, my wife and I moved into a new townhouse condo community. Approaching retirement, I sold much of my system and moved into the world of earspeakers, at a small fraction of the cost of my ultimate system. (Stax amps and earspeakers and a fine CD player)

I must assume that your review process could not extend over the time frame of my listening experience (since my purchase of the WES), so I want to let you know about some long term developments.

When I purchased the SR 009s, Jack suggested that I bring in WES to upgrade the original chokes. (I have no idea what I am talking about)
Immediately I could hear a major improvement. At somewhere between the 200-300 hours of listening experience my audio "troops" and I felt that we had reached the full and final break-in... nirvana! Then, quite unexpectedly, somewhere around 700-800 hours or so, there was a further step into reality. Understand that we had already concluded that "nirvana are us!" But there arrived further clarity... not that we were experiencing any congestion on massed strings, etc., but even more transparancy appeared! On well recorded material, from FIM CDs to hi-res downloads, "YOU ARE ABSOLUTELY THERE"!

Live concerts rarely drive us to greater listening joy except for the participation experience.

ADR

ianmedium -- Sat, 09/29/2012 - 00:54

I have listened to the Eagles track so many times and never got what you heard..Until now! Though I am hearing it through my FAD Piano Forte IX's. That is quite a revelation! Just to be sure I then plugged in my LCD2's balanced and it was not there!

lhissink -- Fri, 11/16/2012 - 05:43

Chris,

Just received my SR009's - and you are correct in your conclusion - they are essentially transparent, transmitting the audio characteristics of the driving chain, and thus potentially frustrating if the drivers are not as transparent as others.

Mind you I was initially startled listening to them to an FM signal during which I heard the musicians sliding their fingers along the frets - heads-up sort of reaction. This information via a standard (low) FM signal ??

That said I'm still running mine in via the Stax SRM600 but bear in mind that this amplifier is being driven by a Qol unit via Accuphase and Bryston sources, so while not Wu's, the driver's are not shabby under most circumstances.

Immediate impressions (Listening to the Decca recording of Ute Lemper) is that this is a very transparent transducer. Switching the Qol in and out has dramatic effects to the soundstage and timbre as well.

Equipment used for this opinion:
1. Computer files produced from DDPoweramp and Audiogate software.
2. Bryston BDP-1
3. Accuphase C2110 preamp with DAC30 option
4. Qol Signal enhancing unit
5. Stax SRM-600
6. Stax SR009 headphones.
7. HP Envy all in one PC, Windows 8, Audiogate Software 4.3 via Accuphase DAC30 SP/DIF USB.

Louis Hissink

Michael Oelgesc... -- Thu, 05/09/2013 - 02:34

I now have the set for almost 1 month. And there was not a single moment, where I have regretted the purchase. For the most part of the last 10 years, I had a Stax SignatureI headphone set with a SRM 006tII energizer. But somewhere along the line, I decided to buy a better headphone set, opted for the SR 009 headphone with the SRM 007tII energizer and bought them. Frankly, when I listened to the new set for the first time, I didn't expect the improvement in quality to be that big. While I always enjoyed the Signature set, the SR 009 really makes a difference in terms of clarity, reproduction of cymbals and basses, etc. And I don't even have a stellar audio system. My Cambridge Audio CD Player 851C is just fine along with some solid main plugs, XLR- and Cinch cables.

In that regard, if you can't afford to be all your stereo components high end, you can make concessions and still be happy. Some 20 years ago, a dealer told me to spent the same amount for player (phone, cassette, CD, tuner), and amplifier combined for the speaker set (in my case the Stax set). I always kept that in mind and in my opinion, he was right.

At last I would like to add, that in my opinion, the SR 009 is worth the 5.000 € you have to spent (in germany where I live).

It isn't easy to quantify, whether money for an item is well spent or not or is worth the amount. In my opinion it depends, what you expect from the item to be bought. When it comes to listened to music and enjoying life, the SR 009 is a good choice.