Overview

Introducing the WA24 20th Anniversary Edition, a masterpiece born from two decades of innovation and passion at Woo Audio.

Twenty years ago, Woo Audio began its journey with the creation of the WA1, an innovative vacuum tube amplifier. Built in a small apartment in Queens, New York, by a father and his two sons, this amplifier was crafted from readily available components sourced from local electronics stores like RadioShack and surplus outlets. The WA1 demonstrated an impressive ability to enhance the sound of the modest Sennheiser HD650 headphones, inspiring the team to pursue new ways to improve the listening experience for music lovers. Now, in celebration of its founding in 2004, Woo Audio proudly introduces the WA24 20th Anniversary Edition. The next chapter begins now.

Redefining the Listening Experience

Built with knowledge from over twenty previous amplifiers, the all-new WA24 is a reference-level amplifier engineered to redefine your headphone listening experience. It brings you closer to the music than ever before, immersing you in the artist’s true intent with stunning clarity and detail. Unveiled in its purest form, every note and every subtle nuance is delivered with breathtaking precision, creating a soundstage so immersive that you’ll feel like the performance is happening live, right in front of you. The anodized gold 20th Anniversary plaque symbolizes Woo Audio’s commitment to producing long-lasting products for a lifetime of musical enjoyment.

A Masterpiece of Design

Every internal component of the WA24 20th Anniversary Edition is carefully selected and thoughtfully laid out for unparalleled sonic performance. At its core are four custom-made 3A/109E mid-gain, direct-heated triode power tubes, chosen for their exceptionally low noise and long-lasting durability. The amplifier’s Class-A single-ended topology ensures the purest amplification possible, while the oversized output transformer—a hallmark of Woo Audio design—delivers maximum power and dynamic range, even for the most demanding headphones.

The WA24 introduces a groundbreaking innovation: the in-house developed STEP-UP Driver. This precision step-up transformer, built with a nano-crystalline core and oxygen-free copper wiring, redefines amplification. By replacing traditional active drivers, such as vacuum tubes or transistors, it simplifies the circuit, reduces interference, and dramatically enhances performance. The two-tier chassis, precision-machined from a single block of high-grade aluminum, balances modern elegance with timeless craftsmanship. Each element is methodically designed for both form and function, with an individually shielded enclosure that minimizes internal electrical noise and microphonics. The result is an extraordinarily low noise floor, making the WA24 one of the quietest and most refined vacuum tube amplifiers ever created.

Enjoy stereo channel precision from the 50mm brass-enclosed ALPS Alpine RK50 potentiometer, integrated into a substantial-feel volume knob housed within a precisely fitted, slotted, curved shield, delivering a tactile experience as refined as the amplifier’s sound. The sandblasted, anodized body flows seamlessly with its contours, while the elegant coke-bottle-shaped 3A/109E vacuum tubes blend classic design with modern sophistication.

Unlock the Future of Sound

The WA24 20th Anniversary Edition is more than a headphone amplifier—it’s the culmination of 20 years of unwavering dedication to design and sonic excellence. This is Woo Audio’s finest creation yet—the amplifier you’ve been waiting for. Experience music like never before.

Highlights

Introduced in September 2024
Latest flagship headphone amplifier
Designed and assembled in New York, USA
Three-year limited warranty [learn more]

REVOLUTIONARY CIRCUIT AND MECHANICAL DESIGN

Single-ended, all-tube design (not hybrid), Class A with zero-feedback operation
Point-to-Point wiring
Two-tier chassis isolates the tube amplifier (top) from the linear power supply (bottom)
CNC-machined aluminum chassis milled out of a solid block of aluminum
Insolated active and passive components achieve the lowest noise-floor
Reduced wiring length through a shortest-path wiring schematic
Self-biasing amplifier

NEXT-GENERATION TECHNOLOGY

Streamlined and refined circuit topology:
Audio input -> STEP-UP Driver -> Single-ended Triode power tubes -> Output Transformer -> Audio output
Direct-heated single triode vacuum tubes in parallel to ensure the purest amplification
Oversized in-house developed output transformers deliver maximum output for the most demanding headphones.
in-house developed STEP-UP Driver delivers unmatched accuracy and the lowest noise floor for the most efficient full-sized headphones and In-ear headphones (IEMs).
The lowest noise floor among our desktop tube amps results in pitched dark background noise with most full-sized headphones, suitable for many in-ear monitors (IEMs)

PRECISELY CHOSEN

Power tube: custom-made 3A/109E vacuum tube in a closely matching quad (4 tubes)
ALPS Alpine RK50 volume potentiometer in a brass enclosure
WBT RCA connectors
Polytetrafluoroethylene (PTFE) tube sockets
PTFE-insulated silver-coated OFC hook-up wires
Audio-grade thin film filtering capacitors in HV power supply

SPECIFICATIONS

Inputs: XLR x 1, RCA x 2
Headphone outputs:
Balanced: 4-pin XLR and 4.4mm Pentaconn®
Unbalanced: 6.3mm (1/4”) and 3.5mm
Frequency response: 10Hz–40kHz
Compatible headphones: 8–600 Ohms impedance and 74dB–120dB sensitivity rating
Finish: black and gold anodized aluminum, sandblasted finish
Compatible AC voltage: 100v – 240v
Power consumption: 40W
Unit Dimensions: 15-1/2” L x 10-5/8” W x 7-1/2” H (390mm x 270mm x 190mm)
Weight: 38 lbs (17 kg)