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Woo Audio WA33


Fully-Balanced Headphone Amplifier

In 2009, we introduced two world-class fully balanced headphone amplifiers––the WES electrostatic amp and the WA22 dynamic amp. Both are preferred choices among the most discerning audiophiles. Here at Woo Audio, we constantly push the performance boundaries. The newly developed WA33 is a state-of-the-art, fully balanced headphone amplifier that raises the bar in setting a new reference in music reproduction.

The WA33 employs a true fully balanced design in a compact form factor, featuring a quad (four) of 6C45 tubes for the driver that pushes a quad (four) of 2A3 tubes for the power, and all in direct-heated triodes. It delivers high power to drive demanding headphones to their full potential while maintaining a low noise floor for use with highly sensitive models. The WA33 shares the same striking appearance of the critically acclaimed WES, where both amplifier units are independent of the power supply. This approach eliminates any interference to critical audio components. Additionally, our internal coupling architecture (ICA) technology allows the WA33 amplifier to merge with the power supply unit without an external umbilical cord. The ICA shortens the signal path and thus significantly reduces unwanted electrical interference and raises sound performance to a level beyond what anyone has previously experienced in a headphone system.

The WA33 reveals the most delicate detail with the highest level of refinement. Complex music passages are handled with ease and authority. The expansive soundstage, holographic imaging, and rich tones that are pristine, natural, and vivid create a sense of realism that gives the user a euphoric listening experience. With the WA33, music comes to life.

  • Same default tubes for all versions: 6C45 driver x 4, 2A3 power x 4, 5U4G rectifier x 1

  • 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

  • Outputs: Dual 3-pin XLR (left and right channel), 4-pin XLR x 1 and 1/4″ (6.3mm), XLR x 1 preamp

  • User selectable output: pre-amp or headphone

  • User selectable HI/LO impedance and HI/LO level for headphone

  • Headphones impedance: 8—600 Ohms

  • Frequency response: 10Hz— 60kHz, -2dB

  • Power output: up to 10 watts per channel @32 Ohms [ideal for power demanding headphones]

  • Signal/Noise: > 95 dB, THD: < 0.05%, 1kHz

  • Anodized aluminum chassis, available in black or silver

  • Self-biasing with compatible tubes [chart]

  • Power consumption: 150w

  • Voltage: AC 100 – 120V 60HZ or AC220 – 240V, 50HZ, voltage built to destination country

  • Dimensions: 17.5″(W), 12″(D), 13″(H) with tubes, weight: 53 lbs for Standard, 56 lbs for Elite Edition. Open for airflow is required for ventilation.

  • Designed and assembled in New York, USA

  • Three-year limited warranty [learn more]