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Overview

WA33 2nd Generation – The Pinnacle of Headphone Amplification

Since its debut in 2017, the WA33 has been recognised as one of the world’s finest headphone amplifiers. As headphone technology evolves and advances, so must the amplifier. Today, we raise the bar with the introduction of WA33 2nd Generation, a new performance benchmark for the next generation of high-end headphones.

True Ribbon, Perfectly Realised

The WA33 2nd Gen is the first of its kind to introduce direct-drive current output for True Ribbon headphones—a technology that bypasses traditional interface limitations.

True Ribbon headphones utilise an ultra-thin strip of aluminium foil suspended in a magnetic field, producing exceptionally low impedance down to just 0.038Ω. As a result, standard headphone amplifiers are unable to drive them directly. An external interface is typically required to raise the impedance to a level compatible with conventional amplifiers. Our direct-drive technology enables WA33 2nd gen to operate at ultra-low impedance upholding the superior sound quality of true ribbon headphones.

The WA33 2nd Gen removes the need for intermediary devices. With a dedicated current-drive output tailored to ribbon headphones like the RAAL Immanis and Magna. The result is a pure, unaltered signal transmission delivering feather-light transients, massive dynamic range, and breathtaking realism. The way we hear music – naturally.

Dual Output Modes for Maximum Compatibility

The WA33 2nd Gen offers two discrete output modes, each optimised for a specific headphone type:

HP Mode: Traditional headphones, such as dynamic and planar magnetic

TR Mode: Current-drive for ultra-low impedance True Ribbon headphones

This dual-mode architecture ensures peak performance across a wide spectrum of headphones, without compromise to signal integrity, resolution, or safety.

Artisan Transformers, Elevated Performance

At the core of the 2nd Gen design are newly refined, in-house output transformers, hand-wound with a precision winding topology. Compared to the original WA33, these deliver a lower noise floor, enhanced soundstage dimensionality, and a more immersive sonic experience.

For the first time, these upgraded transformers enable true current-drive capability, unlocking the full expressive potential of ribbon headphones with commanding authority.

Graceful Power, Immaculate Control

Driven by four 6C45 driver tubes and four 2A3 power tubes in a fully balanced Class-A push-pull configuration, the WA33 2nd Gen delivers up to 10 watts per channel with exceptional clarity and minimal distortion. It handles demanding headphones effortlessly and offers whisper-quiet operation for sensitive models.

A LEVEL switch fine-tunes output to match your headphone’s sensitivity, ensuring the ideal balance of power and finesse.

Elegant Design, Superior Engineering

Despite its commanding performance, the WA33 remains strikingly refined. Its dual-chassis architecture is connected through our proprietary Internal Coupling Architecture (ICA), eliminating external cabling while preserving separation between signal and power.

The result is a design both minimalist and monumental: fewer wires, lower interference, and a cleaner signal path—all housed in an aluminium chassis of sculpted solidity and elegance.

Setting up is effortless: insert the tubes, connect your source, and enter a world of musical realism.

*Note: A conventional amplifier has an output impedance that’s hundreds of times higher than a ribbon driver. Connecting True Ribbon headphones to such an amplifier can cause a short circuit, severely damaging both the amp and the headphones. The WA33 2nd Gen is purpose-built to drive ribbons directly and safely.

Highlights

• User selectable outputs:
  • TR (True-ribbon) direct-drive without interface
  • HP (Traditional headphone)
• Headphone Outputs:
  • 4-pin XLR balanced for True-ribbon (TR) without interface
  • 4.4mm balanced (Pentaconn®)
  • 4-pin XLR balanced
  • 6.3mm unbalanced TRS

• Same default tubes for all versions: 6C45 driver x 4, 2A3 power x 4, 5U4G rectifier x 1
• Self-biasing with compatible tubes [chart]
• Fully balanced design, Push Pull, Class-A
• Polytetrafluoroethylene (PTFE) tube sockets
• TKD (Tokyo Ko-on Denpa) 4-channel balanced smooth potentiometer
• Transformer-coupled, Point-to-Point wiring
• Internal Coupling Architecture (ICA)
• XLR input x 2, RCA input x 1
• User selectable HI/LO impedance for HP headphone
• User selectable HI/LO level for two levels of power output
• Headphones impedance: 0.038—600 Ohms
• Frequency response: 10Hz— 60kHz, -2dB
• Current output (TR):  3.3A [optimised for true ribbon technology]
• Power output (HP): up to 10 watts per channel @32 Ohms [ideal for power-demanding headphones]
• Signal/Noise: > 95 dB, THD: < 0.05%, 1kHz
• Anodised aluminium chassis, available in black or silver
• Power consumption: 150w
• Compatible AC voltage: 100v – 240v
• Dimensions: 17.5"(W), 12"(D), 13"(H) with tubes, weight: 54 lbs for Standard, 57 lbs for Elite Edition. Open airflow is required for ventilation.
• Designed and assembled in New York, USA