Headphones — Stax SR-X9000

The SR-X9000 is a flagship electrostatic headphone from Stax, sharing bandwidth and impedance characteristics with the SR-009D within a somewhat lighter chassis. The SR-X9000 brings Stax's most accomplished current engineering to an open-back electrostatic format.

Key specs that matter

The transducer uses electrostatic or planar-magnetic driver technology in an open-back, over-ear, wired configuration. Frequency response spans an exceptionally wide 5Hz to 42,000Hz within plus-or-minus 10dB, matching the SR-009D. Sensitivity is 100dB SPL at 1kHz/1mW, marginally lower than the SR-009D. Impedance is an extraordinary 145,000 ohms at 1kHz, matching the SR-009D - a characteristic figure requiring a dedicated electrostatic amplifier. Weight is 432g, somewhat lighter than the SR-009D's 452g.

Sound and use context

Expect the exceptionally detailed, precisely engineered character Stax's legendary electrostatic driver technology is broadly celebrated for, closely matching the SR-009D's flagship-tier engineering ambition within a somewhat lighter chassis.

Pairing

The extraordinary 145,000-ohm impedance requires a dedicated Stax electrostatic amplifier, such as the SRM-700S or SRM-700T, using the brand's proprietary Pro-bias connection.

Alternatives

Stax's own SR-009D offers a very closely related flagship electrostatic alternative sharing nearly identical specifications.