Sugden Sapphire FBA-800 Pure Class A Power Amplifier: Ultimate Fidelity in a Floating Bridge Design
The Sugden Sapphire FBA-800 Pure Class A Power Amplifier represents the pinnacle of Sugden’s engineering, designed to deliver unparalleled power and fidelity. This advanced stereo power amplifier features a unique floating bridge design, combining four 20-watt Class A amplifiers in one chassis. This configuration enhances output capability while minimising distortion, resulting in a high-performance amplifier that provides a noise-free, balanced, and immersive listening experience. From its proprietary DC-coupled circuitry to its professional-grade power supply, the FBA-800 is built to deliver exceptional sound clarity and depth, making it ideal for audiophiles and professionals seeking ultimate audio precision.
Floating Bridge Design for Low Noise and High Load Tolerance
The FBA-800’s floating bridge design consists of four amplifiers arranged to maximise output while maintaining a low noise floor. Each channel includes two voltage amplifiers that drive a bridged output stage, providing several advantages over traditional designs. This setup allows the amplifier to double power output relative to its voltage rails, optimising performance across the audio spectrum. With Class A fixed current, the FBA-800 achieves low output impedance and high load tolerance, allowing it to drive a wide range of speakers with precision and ease. This design also minimises signal interference, resulting in a clean and spacious soundstage with minimal distortion.
DC-Coupled Circuitry with Servo Lock for Enhanced Low-Frequency Detail
The FBA-800’s DC-coupled circuit design includes a servo lock, which ensures superior control over low frequencies, providing deep, well-defined bass without compromising clarity. This direct-coupling approach bypasses capacitors in the signal path, maintaining signal purity and delivering natural, distortion-free sound. For added protection, the amplifier includes a DC protection circuit that incorporates low-impedance MOSFET switching devices, safeguarding the amplifier and speakers while enabling a soft power-up and power-down process for seamless operation.
High-Performance Power Supply with Custom-Built Transformer
Sugden has outfitted the FBA-800 with a robust power supply to support its demanding Class A operation. A custom bi-filar wound transformer with four separate windings ensures that each section of the amplifier receives clean, consistent power, improving efficiency and minimising noise. The main smoothing capacitors are specifically developed for professional audio applications, providing exceptional ripple characteristics and longevity. Each channel’s output stage features four multi-emitter power transistors capable of delivering up to 26 amps per transistor, ensuring a reliable, high-current output that meets the needs of even the most challenging audio passages.
Full Balanced Operation from Input to Output
Designed to deliver pure, unaltered sound, the FBA-800 operates in fully balanced mode from input to output. This fully balanced design ensures superior signal integrity by reducing noise and eliminating interference, resulting in a cleaner, more precise audio output. The front panel includes a gain selector with a 6dB input attenuation option, allowing fine-tuning of input levels, and an input selector for choosing between RCA and XLR connections, enhancing compatibility with both balanced and unbalanced sources.
Superior Audio Specifications for Ultimate Sound Reproduction
The FBA-800’s technical specifications highlight its focus on sound fidelity. With a frequency response of 20Hz to 80kHz and a bandwidth reaching 113kHz, this amplifier captures every detail within the audio range. Its signal-to-noise ratio of over 96dB ensures ultra-quiet operation, while distortion at 1 watt and 1kHz remains impressively low at less than 0.05%, preserving the integrity of the original recording. The amplifier’s input sensitivity is set at 735mV for full output, optimising compatibility with various pre-amplifiers and high-quality sources.
Durable Build with a Refined, Functional Design
Encased in a sleek yet robust chassis, the FBA-800 weighs in at 25kg and measures 206 x 430 x 460mm, reflecting its substantial build quality and dedication to performance. Its elegant, minimalist design makes it a visually appealing addition to any high-end audio setup. With multi-way locking binding posts for secure speaker connections, the FBA-800 combines durability with ease of use, ensuring long-term reliability and consistent performance.
The Sugden Sapphire FBA-800 is ideal for audiophiles seeking a high-powered, flexible, and pure Class A stereo amplifier that captures the full spectrum of musical detail. Its floating bridge design and balanced circuitry make it an exceptional choice for those looking to elevate their listening experience with the best of Sugden’s audio engineering.
