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SR-X9000

Driver
Electrostatic
Enclosure
Open-back
Weight
432 g
List
$6,200
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Stax's flagship electrostatic, with a four-layer fixed electrode bonded by thermal diffusion and a diaphragm 20% larger than the SR-009S. The guard mesh is tilted so it is never parallel to the diaphragm.

Where to buy

List $6,200

Retailer prices checked 2026-10-21. We may earn a commission on purchases. How this works

Title block

Maker
Stax
Model
SR-X9000
Made in
Japan
Released
2021
Transducer
Electrostatic
Enclosure
Open-back
Driver
Not published
Weight
432 g
Impedance
145 kilohms
Sensitivity
100 dB / 100 V r.m.s. at 1 kHz
Frequency response
5 Hz – 42 kHz
List price
$6,200 USD

Assembly drawing

12345678

Parts

  1. 1HeadbandStainless steel arc with aluminum stabilizer; genuine-leather head pad
  2. 2YokeStainless steel arc assembly; 9-step click slider; cable inlets angled forward
  3. 3GrilleTilt guard mesh, posts of different front and rear height
  4. 4FrameMachined aluminum enclosure
  5. 5Rear statorMLER-3 stator: four-layer fixed electrode, metal mesh plus etched electrodes, diffusion-bonded
  6. 6DiaphragmUltra-thin super-engineering plastic film, area 20% larger than SR-009S
  7. 7Front statorMLER-3 stator: four-layer fixed electrode, metal mesh plus etched electrodes, diffusion-bonded
  8. 8EarpadsGenuine sheepskin (skin contact), artificial leather (mounting portion)

Schematic electrostatic assembly, annotated with the Stax SR-X9000’s published materials. Not to scale.

Engineering notes

  • MLER-3 four-layer fixed electrode bonds metal mesh and etched electrodes by thermal diffusion bonding
  • Diaphragm area 20% larger than the SR-009S
  • Tilt guard mesh with posts of different lengths so the mesh is never parallel to the diaphragm
  • Stainless steel arc assembly; 6N OFC plus silver-plated copper cable, 2.5 m and 1.5 m supplied

Design language

Rectangular enclosures machined from aluminium on a stainless steel arc, with sheepskin where it touches your head.

Build the listening station

Desktop sanctuary

Electrostatic drivers run from a dedicated high-voltage energizer. Pair it with an energizer from the maker or an electrostatic specialist.

Related architecture

Sources