Quad 303 Power Amplifer (2024 Edition)

Evolution of the QUAD 303
Every aspect of the QUAD 303 Power Amplifier has been re-engineered beyond a simple update of components. Originally designed for domestic use, it also became a favourite in broadcasting and recording studios for its reliability. The new model surpasses the original’s standards while maintaining its ethos, with modern design and functionality that reflect its enduring appeal, even earning a place at the Museum of Modern Art.

Technological Advancements
The QUAD 303 stays faithful to its roots with QUAD’s ‘symmetrical triples’, ensuring low distortion and stable performance under dynamic conditions. This advancement means distortion levels are now almost negligible, far below what is detectable by the human ear. The ‘triples’ design also protects the output transistors, enhancing reliability without complex circuitry.

Complementary Output Stage
Unlike the original’s quasi-complementary stage, the new QUAD 303 employs a fully complementary output stage, using premium transistors for better linearity and stability under challenging conditions. With this, the amplifier handles overdriven or disconnected speaker scenarios effortlessly, maintaining excellent sound quality and reliability.

Modern Features and Power Output
The new QUAD 303 incorporates a custom low-noise toroidal transformer and the amplifier’s design remains iconic, with durable materials and rugged construction that offer both style and substance. However, with some tweaking and enhancements, the 303 is loaded with a little extra power – offering 50W @ 8 ohms (70W @ 4 ohms) with a maximum current delivery of 10A into difficult loads. The original 303 was known to have issues with lower impedance loads, the new 303 has no such trouble. Perfectly suited to the more demanding requirements of the modern audiophile, it ensures any speakers – even including QUAD’s electrostatic designs – can be driven with ease. Connectivity options comprise single-ended RCA and balanced XLR inputs, a 12V trigger input and high-quality speaker binding posts. Simple, solid and thoroughly authentic, inside and out. The power output for 'bridged mode' (for use as a mono-block power amplifier) reaches 140W @ 8 ohms or 170W @ 4 ohms (bridged mono).

QUAD’s Legacy and Modern Excellence
By revisiting the QUAD 33 and 303 components, QUAD reaffirms its longstanding legacy in the British hi-fi industry, blending authenticity, pedigree, and innovation. This new iteration pays homage to QUAD’s past while showcasing its excellence in modern audio engineering. The QUAD team involved in this project possesses nearly 200 years of combined engineering experience and over 100 years dedicated to QUAD’s unique designs and service, further reinforcing the brand’s enduring commitment to quality.

The Team Behind the Innovation
The development of the new QUAD 33 and 303 was overseen by a team of experts, including Rob Flain and Paul McConville, two of the most experienced QUAD service engineers. Jan Ertner, with three decades of QUAD design expertise, Peter Comeau, the mastermind behind some of QUAD’s most successful loudspeakers, and David McNeill, who has been at the forefront of QUAD’s innovations for two decades, all played key roles. Together, they ensured that the new products could uphold the legacy of the iconic 33 and 303.

Specifications

Weight - 8.4kg
Dimensions (HxWxD) - 325mm X 176mm X 120mm
Technical specifications
THD - <0.002% (1kHz)
Frequency response - 20Hz - 20kHz (+/-0.3dB)
Input sensitivity - 700mVrms (Line) 1.5Vrms (XLR)
Input impedance - 10k ohms
Gain - +29dB
Inputs/Outputs
Inputs - 1 x Line, 1 x XLR
Outputs - 1 x 12V Trigger 1 x Stereo Speakers, 1 x 12V Trigger Link.