New flagship earspeakers equipped with newly fixed electrode MLER-3 technology. SR-X9000 is the new flagship Earspeaker that marks the pinnacle of Stax electrostatic headphones production. A major technological advancement is the “MILER-3” (Multi-Layer-Elect-Rords) - a four-layer fixed electrode combining mesh electrodes and conventional etching electrodes that are crimped by thermal diffusion bonding. The newly developed manufacturing technique matures through a 20-year accumulated research and development, allowing a rigid structure that is resistant to resonation while smoothly evolving sound transmission characteristics compared to conventional multilayer fixed electrodes. A product development story: the circular metal mesh once mounted on the SR-X was one of the ideal electrodes to reduce the effects of air resistance and reflections and increase sound permeability. However, there was a big hurdle in installing metal mesh electrodes in products because they lack strength and are resonant-prone that, causes playback sound to become muddy. In the 1990s, the original SR-Ω was developed to increase the size of the metal mesh; however, the manufacturing technique was at its infancy as it was impractical to produce stable products. As a matter of fact, there was only a few pairs of SR-Ω were made. The SR-X9000 diaphragm is made of ultra-thin engineering film that is 20% larger than the previous flagship SR-009S. The diaphragm mass has been reduced to create a lightning-fast reaction speed and high-frequency response range that elevates headphones listening to a new level. The diaphragm is made of ultra-thin super engineering plastic film. Due to weight saving close to zero, great transient characteristic is realized. From the base to the high range, the linearity of the sound is improved. The area of the diaphragm increases by 20% compared to SR-009S. This breakthrough realizes the widest sound field ever. 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 improved acoustic characteristic inside the enclosure realizes clearer sound unaffected by sound reflection. The guard mesh which is installed parallel to the sound element 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 lengths in front and back. This design changes the height of the gap between the sound element and the guard mesh. So the guard mesh cannot be parallel to the sound element and the reflection angle is completely controlled. The sound wave flows smoothly. The main material of the arc assembly is upgraded to stainless steel. The arc assembly is more tolerant to torsion and the earspeaker more stably fits your ears. The material of the head pad which directly contacts to the skin is genuine leather. The position can be adjusted by the slider parts with 9 step clicking system. The material of the ear pads is genuine leather (sheep skin) which has excellent breathability and softness. Genuine leather makes the earspeaker to closely fit your ears for a long time and you can fully enjoy the high-quality bass and vivid sound. This also reduces fatigue and you can comfortably listen to music for a long time. The material of the core cable is a 6NCu ultra-pure annealed copper wire (φ0.14×3). The material of the around core cable is a silver-plated annealed copper wire (φ0.08×９). So high and low frequency is improved. The cable can be changed (recable). 2 cables (2.5m and 1.5m) are attached and you can choose the cable according to your listening style. The storage case is made of “paulownia wood” which has low thermal conductivity and humidity control capacity. This case is the best storage solution.