Sugden Masterclass LA-4

Sugden Masterclass LA-4

High-End Active Preamplifier

The LA-4 is a high-end active preamplifier designed for audiophiles who demand exceptional sound quality, uncompromising engineering and complete system flexibility. Engineered to partner perfectly with both the Masterclass and Sapphire power amplifiers, the LA-4 delivers outstanding musical performance while acting as the control centre of a reference-quality hi-fi system.

Featuring a comprehensive selection of analogue inputs and outputs, the LA-4 allows effortless integration with premium source components, power amplifiers and other high-end audio equipment. Every signal path has been optimised to preserve musical integrity, ensuring that every recording is reproduced with exceptional clarity, accuracy and realism.

The Sugden Masterclass LA-4 incorporates numerous premium engineering features that distinguish it from conventional preamplifiers. Gold-plated circuit boards provide superior conductivity and long-term reliability, while precision relay switching ensures silent, accurate source selection with minimal signal loss. These carefully considered design choices help maintain the purity of the audio signal from input to output.

A sophisticated Class A output stage lies at the heart of the LA-4, delivering an ultra-low-noise performance with exceptional linearity and transparency. The result is an active preamplifier capable of revealing the finest musical detail, expansive sound-staging and natural tonal balance while maintaining effortless control during even the most demanding musical passages.

Designed as a high-gain preamplifier, the LA-4 provides exceptional drive capability and authority over virtually any compatible power amplifier. Whether reproducing delicate acoustic performances or large-scale orchestral recordings, it delivers outstanding dynamics, precision and control across the entire frequency range, allowing music to be reproduced with remarkable realism and emotional engagement.

Every element of the electronic circuitry has been developed with one goal: preserving the original audio signal without compromise. Specially selected low-noise transistors and premium-grade capacitors have been chosen for their sonic characteristics, helping minimise distortion while maximising detail, transparency and musical expression. This meticulous component selection enables the LA-4 to deliver a pure, natural and highly resolving listening experience.

Each gain stage is powered by an advanced current shunt differential power supply, providing an exceptionally stable source of clean power. This sophisticated power supply architecture enables lightning-fast transient response, superb dynamic range and effortless reproduction of powerful musical crescendos without compression or loss of detail. The result is a presentation that combines speed, authority and refinement with genuine musicality.

Whether forming part of a dedicated two-channel hi-fi system or a reference-level audiophile setup, the LA-4 active preamplifier offers exceptional build quality, advanced analogue engineering and world-class sonic performance. Combining precision, transparency and effortless control, it is the ideal choice for music lovers seeking a high-end preamplifier capable of unlocking the full potential of their audio system.

Sugden Masterclass LA-4 Technical Specifications

Inputs​ – Four line level inputs, one tape input, one balanced input, bypass input

​Outputs – Two line level outputs, fixed tape output, balanced output

Volume Control – Motorised remote control RC5 Compatible

Recording – Tape output defeat​​​​​​

Input Sensitivity -100mV for 1 Volt out

Maximum Output​ – 10 Volts​​

​​Frequency Response – +/-0.1dB 15Hz-30kHz

Bandwidth – 6Hz-300kHz

Signal to Noise ->90dB

Distortion – <0.006% @ 1kHz, 1 Volt out

Gross Weight (packed) – 7kgs

Dimensions – 75 x 430 x 350mm (hwd)