Stax SR-009 Electrostatic Headphones

Knowing where to begin describing these is hard. The closest I can come is my first experience listening to a pair of full-size swiss Piega loudspeakers back in the early '90s. The resolution of those things was so incredible I thought that they reproduced the notes of a double-bass with such amazing resoultion you could hear the detail of the strings vibrating and that's before you get an idea of what their ribbon tweeter could do! Similarly, I recently experienced the capabilities of the Linn Klimax Twin power amp on a variety of speakers. The absolute authority and perfection of its presentation was something to behold and it immediately drove me to wonder how it might be possible to afford one.

Similarly the 009s have had such an effect on friends who have listened to them. Much like the Omega IIs and a suitable high-end rig, it is possible to make out the form of the studio music was recorded in by the detail of the echo off the walls. Listening to a classical concert I can even hear the detail of the waves of echos from the instruments coming off the walls. With these earspeakers, as Stax terms them, it is as if everything is simply on another level compared to dynamic headphones. Only the more recent high-end orthos, such as the LCD-3s and Hifiman series and maybe the HD-800s, Sony R10s and my Symphones Magnums come anywhere close. Now the SR-009 takes all this to yet another level. In the same way the first time I tried Stax and compared them to my regular headphones everything was so much more clear and real, the 009s have achieved this over even the orthos, which I hold in the highest regard. Questions about resolution, harshness, distortion, ringing and other issues simply seem not to exist.

While Stax will never give quite as much impact, or slam to music as othos can (while maintaining a high level of detail), the orthos, already awesome in this regard, especially with something like a high-end hybrid amp, wont give you instruments and voices with as much clarity as 009s, if they are arguably better all-rounders. The limits are only set by your source and amp, especially the former. I could easily visualise a $25k system with a pair of these (along with a Liquid Lightening or Blue Hawaii SE and Esoteric K-01 DAC).

Tonality-wise they are similar to the old-style Omega I and Lambda, that is, quite a bit brighter than the Omega II, which was always the odd one out in terms of sound. They suffer, like other models, from the "Stax fart" where moving your jaw and breaking the seal causes the protective membranes to make a sucking sound. However, like the original Omega and unlike the Omega II, they seem to be less difficult to drive, with detailed bass even from the older amps, such as the T1S. A good combination I found was the NOS Metrum Octave DAC, which is relatively mellow but still detailed, along with the Stax 727A amp. This gave a number of people an OMG moment listening to acoustic music, though it was not quite the ticket for rock. The bass, like the power output of a Rolls Royce, is "sufficient". The LCD-3 I found more entertaining in that regard.

They are again similar to the Omega I in that they come in an elegant wooden box with the nicest foam of any box I've encountered in recent memory. Opening it up, I was greeted with a "new car" smell, suggesting they source the leather from a factory that makes car seats. The headband has a new 10-click (per side) adjustor, which is quite stiff to adjust but holds firm unlike the old Lambda headbands. Beyond that, the fit is typical Stax -- light and comfortable. The aluminium design is of the highest quality, if it does seem to contrast the rather simple headband arrangement. Like its maker, it is in many ways an understated design, its statement in its perfection of design and sound.

So, ultimately, we have our king. Long live it and its maker I reckon.

(Updated June 23, 2012)

As the subjective sound quality of the SR-009 has been extensively discussed in the other reviews, I will focus on my objective experiences. Whenever I purchase new high-end products, I always choose to run a blind test consisting of the model in question alongside other high-end headphones. This time, the comparison counterparts included the LCD-3, HD800, HD650 and Orpheus. 

 

My subjective impressions always tend to take a similar route: there exists a very strong correlation between the price tag and the sound quality that I perceive. It was no different this time. Therefore, I performed the blind test on ten participants who are all fellow classical musicians in a blindfolded setting (with the volume matched etc).

 

The results this time were indeterminate. However, the HD800 came last followed by the Orpheus. After the blindfolds were removed, the Orpheus was unanimously agreed as having the best sound quality (the Orpheus does look rather magnificent). The Stax was chosen to have the best sound quality by three people.

 

This kind of test demonstrates that all these high end headphones do not have such a huge disparity in sound quality as made out by other subjective reviews. Therefore, I am always slightly let down by products with such a steep price tag as the Stax. Evidently it is not as steep as the Orpheus, however, for this money, I believe it is more worthwhile buying a pair of speakers.

 

I believe it is also important to stress that the superlatives associated with this headphone should be taken with a grain of salt, in fact several pounds would suffice. I do not think that the SR-009 sounds bad. On the contrary, I believe it sounds fantastic (I had very similar experiences to Currawong's review). However, as this test has demonstrated, it does not outperform other high end counterparts with noticeable significance (this is especially noteworthy as the other test headphones except for the Orpheus are considerably cheaper than the Stax). 

 

Hence all in all, I believe that the SR-009 is an outstanding piece of gear, but by no means the King of headphones.

First of all they are drop-dead gorgeous and an extremely high quality construction. I have not seen any headphone close to this type of quality feel. It can't be described. When you hold these you won't want to let them go. They are a stunning masterpiece in this regard. They make every other headphone feel cheap. Just... wow. Top that with superb comfort and you've got a an object that will send small pulses of pure joy through your body every time to come in contact with it. 

 

The sound of these headphones didn't wow me the way I was expecting. I've come to the conclusion that no headphone is physically capable of delivering music with quite the level of realism a great pair of loudspeakers can. After all the very positive reviews I was expecting a sound that would knock me off the chair. Well, that didn't happen. But these are still a fabulous pair of high-end headphone goodness.

Having heard a lot of high end headphones and several STAX models I can say the SR-009 sounds more like a perfected version of the old Lambda sound signature than a shot for a warmer, more honey-rich sound like the SR-007.

 

The first thing that struck me was the level of precision with which these played the bass notes. I don't think I've heard a headphone with bass that sounds this distinct and precise before. Über-tight, lightning fast, hard-hitting, very clear and with excellent extension, these have the best bass reproduction I've heard in headphones alongside the LCD-3, which provides (even) better low-end extension and a more visceral, realistic heft. It's a matter of taste, I would say. 

The top-notch clarity and precision continue to the midrange and treble, during my short listening sessions I found no hint of even the slightest grain or imperfections. These are, if anything, extremely even sounding. No peaks or dips, nothing stands out. Everything just comes together. 

I could write more on the different aspects of the sound, and the sound-stage and imaging (which are both top-class as well) but I really see no point in it. These excel in every way, and their pride is not in how they do everything so extremely well, but in how they do so little wrong.

If you're looking for the most technically perfect headphone available, this is the one without question. A friend of mine prefers the sound of the SR-007, stating the warmer, more chesty sound on offer there is the more true to life. Personally I find the midrange of the SR-009 more distinct and up-front, with greater depth of field that gave a better sense of the space and air to vocals and instruments. It sounded more "real" to me. 

So far, I've only heard one case where audio equipment managed to reproduce a perfect human voice. That honor goes to MBL's X-treme loudspeakers connected to 2 pairs of their reference power amplifiers and their reference CD-player and pre-amp. That system is almost $200 000, if I'm not mistaken. The SR-009 doesn't come anywhere near that realism, and that is their biggest flaw. They are still headphones, and considering their cost which can grow to astronomical numbers depending on what source/amp you plan on buying for them, that may be something to be aware of.