US retail price: 4600$ (estimated)
Expected availability: July 2018
This top model of open-ended electrostatic headphones is a challenge for the most demanding audiophiles, requiring uncompromising sound reproduction quality across the 5 Hz to 42 kHz frequency band. Thanks to the new generation of thinned Electrode Membranes (MLER2), the new geometry of air reduction holes and its gilded surface, which with its high specific gravity even further suppresses unwanted vibrations, brings the headphones perfectly balanced reproduction even in the area of the deepest frequencies. All-metal aluminum earcups basically eliminate undesirable resonances. The headphones are designed exclusively for connection to any STAX desktop power amplifier.
Sound element with new fixed electrodes
If the fixed electrode becomes much thinner, the air resistance will be decreased and the permeability of sound waves will be improved. On the other hand, thinner electrodes are poor in rigidity and suffer from vibrations of their own and the sound becomes muddy.The SR-009S evolved further the electrode established in the SR-009 as the integration of present technology.
The edges of electrode hole were smoothened through after-etching processing to reduce air resistance, and the permeability of sound has been improved even more. Moreover, gold plating processing with large specific gravity further decreased the electrode vibration. Finally, the sound clarity has been achieved by reducing the resistance of the electrode itself.
Tough solid aluminum chassis
It has been attached more firmly to the sound element, contributing to improve the clearness of sound. Furthermore, case thickness has been reduced to the limit, for a smoother flow of condensation-and-rarefaction airwaves from the transducer.
Newly designed metal guard mesh
Intensity has been increased by giving roundness to the “guard mesh” of the sound element, which lowered the influence of reflection and improved the resolution.
Thinner, more acoustically transparent protective fabric has been adopted in the new earpads.
Official product page (with specifications)
First short listening impression with factory visit in Japanese (translation available)
Oneguy's short listening impression
HugoFreire's short listening impression
Arnaud's short listening impression
Head-fi TV video
In short, a warmer, smoother, fuller, but even slightly more detailed headphone compared its SR-009 sibling, which will remain in production alongside this new SR-009S variant.