The Flagship Debut: STAX SR-009D Electrostatic Earspeakers

In the world of high-end audio, some products do not just fade away; they become benchmarks. The original STAX SR-009 was exactly that. For over a decade, it was the gold standard for transparency. With the global debut of the SR-009D, STAX has brought back the soul of that original flagship while addressing the practical requirements of the modern audiophile.

The core of this earspeaker remains the MLER (Multi-Layer Electrodes) technology. This process involves unifying three stainless steel plates at the atomic level through thermal diffusion bonding. This results in an electrode with exceptional planarity and high sound wave transmission, delivering the speed and holographic soundstage that defines the STAX legacy.

The Practicalities of Performance

While the internal technology remains focused on acoustic purity, the external chassis has undergone a significant transformation. The most anticipated update is the detachable cable structure. This enhances the usability of the earspeakers by allowing for future compatibility with high-quality cables and simpler maintenance.

To experience the full potential of this electrostatic system, the SR-009D must be paired with a reference-grade driver unit. We recommend the STAX SRM-700T Vacuum Tube Driver for those who prefer a touch of organic warmth, or the flagship STAX SRM-T8000 for absolute authority and control. For a complete desktop solution, these are often paired with a Chord Electronics DAVE to ensure the signal remains uncompromised.

STAX uses the term earspeaker because they believe their ultra-high fidelity devices should only be compared with the best cost-no-object loudspeakers, not other headphones.

Handcrafted Comfort

Luxury is a tactile experience. The SR-009D features ear pads handcrafted from genuine sheep leather on the contact surfaces, providing a breathable and soft fit for hours of music enjoyment. The new 10-step click mechanism on the headband allows for a much more precise and repeatable fit than the older friction designs, ensuring the weight is perfectly distributed across the head.

The Listener’s Verdict

The STAX SR-009D debut is for the listener who demands an unrestricted window into their music. It is the perfect gateway to the world of high-end electrostatic audio, offering a sound that is both incredibly detailed and relaxed even at higher levels. If your collection deserves to be unravelled rather than just played, this earspeaker is the mandatory next step.

The "D" version adds a detachable cable system, a lighter injection-moulded unit case, and an updated 10-step headband for better comfort and serviceability.
As an electrostatic system, the SR-009D requires a bias voltage of 580V DC and must be used with a dedicated STAX driver unit.

​​Ready to hear the pinnacle of personal audio? Visit the showroom to experience the STAX collection.

Read the full review here.