Some products quietly disappear from catalogs, others from collective memory. And then there are models like the STAX SR-009, which continue to live on as a reference even after their disappearance. With the new SR-009D, STAX is bringing back exactly this classic – technically closely based on the original, yet carefully modernized and repositioned at a more attractive price.
The historical background is quickly told: The original SR-009 was considered the high-end reference model in the STAX range for years. With its large, round diaphragm and elaborately manufactured fixed electrodes, it decisively shaped modern electrostatic culture. Today’s flagships such as the SR-X9000 are also conceptually based on this foundation. When the SR-009 was finally discontinued, it left a noticeable gap – and a loyal fan base that repeatedly asked for a return worldwide.
With the SR-009D, STAX is now responding to exactly this demand. The new electrostatic headphone remains true to the original concept, but receives targeted detail adjustments. Housing color, material appearance and cable have been revised, while the basic technical approach remains the same. At the same time, the launch price is below the level of the original SR-009, which makes the 009D a comparatively affordable entry into the upper STAX league for many music lovers.
Sophisticated Converter Technology
The central element remains the MLER (Multi Layer Electrode) technology, which was first used in the SR-009 in 2011 and is still a trademark of STAX top models today. The photo-etched electrodes are thermodiffusion-bonded under vacuum at the atomic level – an extremely complex manufacturing process that ensures high planarity, controlled resonance behavior and an exceptionally clean sound image. In practice, this manifests itself in high transparency, excellent fine dynamics and a remarkably relaxed reproduction even at higher levels.
The SR-009D works as an open push-pull electrostatic with a specified frequency range of 5 to 42,000 Hertz. With a sound pressure sensitivity of 101 decibels and the STAX-typical bias voltage of 580 volts DC, it is clearly designed for operation with suitable STAX driver amplifiers. The technical finesse remains largely invisible, but shapes the confident, finely resolved character of the reproduction.
A practically relevant update concerns the replaceable cable, which the SR-009D takes over from the current model generation. A parallel, six-core, low-capacitance OFC broadband cable is used. The removable design not only increases everyday usability, but also opens up scope for later upgrades.
STAX remains true to its proven line in terms of wearing comfort. The ear pads combine genuine sheepskin leather on the skin-contacting surfaces with synthetic leather in the outer area. With 452 grams, the open electrostatic remains easy to handle despite its size, especially as the generous padding and the typical STAX fit favor long listening sessions.
The STAX SR-009D continues to be manufactured in Japan. All in all, it combines the aura of a modern classic with the practical improvements of the current generation: proven electrostatic technology, updated details and a price that makes access to the STAX reference class easier.
The STAX SR-009D is available now. The recommended retail price is 3,700 euros.
Technical data: STAX SR-009D
Type: Push-pull electrostatic, open
Frequency response: 5 – 42,000 Hz
Sound pressure sensitivity: 101 dB
Bias voltage: 580 V DC
Cable: removable, 6-core, OFC
Cable length: 2.5 m
Weight: 452 g
Manufacturing: Japan
