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Woo Audio ES8


Fully-Balanced Electrostatic Headphone Amplifier

Music lovers have trusted Woo Audio amplifiers to power their headphones since 2004. Our pure tube electrostatic headphone amplifiers have served a vast number of electrostatic headphone enthusiasts around the world for 15+ years.

Introducing the all-new ES8 electrostatic headphone amplifier and preamplifier. Created with the goal to extract the most performance out of electrostatic headphones while being compact in size at an obtainable price for all music lovers.

Similar to most Woo Audio’s dynamic headphone amplifiers, the ES8 utilizes a pair of custom-made output transformers. The output transformer is a crucial part in converting energy from the tubes to provide a high-voltage output required to power electrostatic headphones. We spent immense efforts in developing output transformers that are low-loss, highly efficient, and to deliver an unparalleled sonic performance.

The ES8 employs four EL84 power tubes, which are wired in triode, in a matched quad. They are driven by four low-noise, low-microphonic 8532 JAN tubes that are also in a matched quad. The tube configuration achieves a fully balanced circuit for accurate channel balance, precise imaging, and a vivid soundstage. The tubes are staggered to give the user a clear view of their warm glow enhancing the enjoyment.

The all-aluminum chassis is a precision machine-CNC with a brushed finish that is visually timeless and maintenance-free. The power and output transformers are suspended inside the chassis to reduce electrical interference and the entire circuit is mechanically-tuned for an incredibly low noise floor so you’ll hear more details in your music.

ES8 is built to last. Every component is carefully chosen for the best sound. The amplifier is compatible with all PRO-bias (580v) electrostatic headphones from your favorite brands such as STAX, Audeze, HiFiMan, Dan Clark Audio and others. This state-of-the-art vacuum tube electrostatic headphones amplifier doubles as a preamplifier. Expanding your audio system to speakers is easier than ever with ES8.

  • Fully-balanced electrostatic headphones amplifier, compatible with Audeze CRBN, STAX, HiFiMan Shangri-la Jr., Dan Clark Audio VOCE electrostatic headphones

  • Tubes: EL84 power x 4, 8532 driver x 4

  • Polytetrafluoroethylene (PTFE) tube sockets

  • Push-Pull direct drive, Class-A

  • Partial Point-to-Point wiring

  • RCA input x 1

  • XLR input x 1

  • XLR pre-out x 1

  • Two STAX (Pro Bias) 5-pin EarSpeakers output

  • Maximum output:

  • ALPS potentiometer and power switch

  • Anodized aluminum chassis in black and silver color

  • Self-biasing with compatible tubes [chart]

  • Operating AC voltage: 115v – 230v (voltage below 115v requires step up transformer)

  • Power consumption: 90w

  • Dimensions: 5.5″(H), 12.5″(W), 9.5″(D), Weight: 26 lbs (11.8kg)

  • Designed and assembled in New York, USA

  • Three-year limited warranty [learn more]