STAX SR-X9000

Still the reference, STAX prefer to be know as ‘ear speakers’ rather than headphones, and a quick listen gives you

What is the ideal electrostatic earspeakers? A fixed electrode which reduces air resistance and the effect of reflection. This electrode also has the high sound transparency. This vision was already found in the metal-mesh electrode of SR-X, which was released in 1970. After that, STAX challenged to realize metal-mesh electrodes for SR-Ω in 90’s again. However, the big metal-mesh electrode was difficult to manufacture. So, the mass production was extremely difficult. This is why SR-Ω was produced in small quantities even though this product has high quality sound.

Evolution to “MLER-3”
20 years have passed since SR-Ω was released. In the meantime, the manufacturing technology of metal-mesh was improved. And through the development of SR-009, the know-how of manufacturing multi-layer fixed electrodes evolved. These factors realized the new flagship “SR-X9000”. “MLER-2”, which was installed in SR-009S, evolved into the four-layer “MLER-3”. An etching electrode and a metal-mesh electrode are bonded using the diffused junction (thermocompression bonding). After 2 generations of STAX flagship models, STAX’s manufacturing technology makes a significant contribution to the stable mass production of big round shaped metal-mesh electrodes. For MLER-3, sound transparency evolved more smoothly than conventional multi-layer fixed electrodes. And the rigidity characteristic resistant to vibration also evolved.

Passion for metal-mesh
The round shaped metal-mesh which was installed in SR-X reduced air resistance and the effect of reflection. This increased the sound transparency. So, metal-mesh is the ideal material of fixed electrodes. However, bigger and thinner metal mesh electrodes are poor in rigidity and may make sound unclear. This is the reason why it was too hard to install metal mesh electrodes in STAX products. In 1990s, SR-Ω, in which the metal mesh electrode is installed, was developed. Because the metal mesh electrode was made bigger for this model, it had to be reinforced with an adhesive by hand. This is a very high precision work. So, it was extremely difficult to manufacture metal mesh electrodes for SR-Ω. The stable mass production could not be realised. This is the reason why SR-Ω was sold in very small quantities in spite of its high sound quality.

The diaphragm increases 20% in size compared with the previous flagship model
The diaphragm is made of ultra-thin super engineering plastic film. Due to weight saving close to zero, great transient characteristic is realised. From the base to the high range, the linearity of the sound is improved. The area of the diaphragm increases by 20% compared with SR-009S. This breakthrough realises the widest sound field ever.

The enclosure which is made of tough machined aluminum eliminates unnecessary vibrations
The enclosure of the sound unit is made of tough machined aluminum. This new design firmly fixes the sound unit and completely eliminates unnecessary vibrations. The sound wave from the unit flows more smoothly. The acoustic characteristic inside the enclosure is improved to realize clearer sound unaffected by sound reflection.

The tilt guard mesh design
The guard mesh which is installed parallel to the sound unit generates the direct reflections which affect a bad influence on the sound. This problem is solved for SR-X9000. The guard mesh has pillars of different heights in front and back. This design changes the height of the gap between the sound unit and the guard mesh. So, the guard mesh cannot be parallel to the sound unit and the reflection angle is completely controlled. The clear sound which is not affected by reflection is realised.

Specifications