> Sugden Audio Sapphire FBA-800 Floating Bridge Pure Class ‘A’ Stereo Power Amplifier

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Sugden Sapphire FBA-800 Floating Bridge Pure Class ‘A’ Stereo Power Amplifier

The Sugden Sapphire FBA-800 Pure Class ‘A’ Stereo Power Amplifier further enhances Sugden’s standing and reputation amongst discerning music lovers.

Sugden’s main objective in developing the FBA-800 has been musical performance coupled to a practical user interface, pride of possession and product longevity.

The market trends for new and fashionable technologies have not been ignored and the FBA-800 has been developed to complement and present the user with the very best euphonic experience.

As with all Sugden Products they are designed and manufactured by Sugden in its West Yorkshire, England premises. The use of through hole as opposed to surface mount components, where possible, enhances product life, performance and reliability.

Sugden has extensive experience in Class ‘A’ amplification and overwhelming belief in the sonic advantages of Class ‘A’ operation.

The FBA-800 is a, Floating Bridge Power Amplifier operating in Pure Class ‘A’ output mode. Power output is set at 40 watts / channel, the unit’s toroidal transformer is rated at 350va. The Amplifier has the input facilities of: Balanced Input or Phono/asymmetric input, (both stereo pairs) Output is through a Stereo pair of Speaker Binding Posts.

Selected optional facilities are:

Input sensitivity: this can be reduced in one step by -6dB. This allows the user to adjust the balance/ matching of the Audio, chain, i.e. PreAmp – Power Amp,- Loudspeakers. The sensitivity is selected by Push Button, located on the front Panel.

Balanced or Phono/RCA input: is also exercised by a Push Button on the front Panel.

The FBA-800 Power Amplifier is a Stereo, Class A amplifier operating in the Bridged Mode with the Output earth Floating. Each channel consists of two amplifiers working as voltage amplifiers driving an output stage of Bridged Power transistors. The advantages are a low noise floor, better power output relative to the voltage rails (x2) and with the fixed current of the Class A mode, low output impedance and better load tolerance. The Amplifier has been designed for modern high efficiency loudspeakers.

The Power amplifier is D.C. coupled, with a servo lock, ensuring excellent low frequency detail. For safety purposes the amplifier includes a d.c. protection circuit. This circuit is statically switched using extremely low impedance Mosfet switching devices. This circuit also soft switches the Power Amp On and Off.

The power supply is a low impedance design with a single custom made bi-filar wound transformer, with four separate windings, The main smoothing capacitors for the output stage are specially developed for professional audio applications with excellent ripple characteristics and long life. The Four power transistors per channel in the output stages are multi emitter devices with an output capability of 26 amps per device.

The FBA-800 operates in the full balanced mode from the input of the unit to the output. This is accomplished by using the two amplifiers per channel in the balanced mode. For people who want to experience all the emotions of music this Amplifier is set completely in Class ‘A’. No compromise has been taken with the build quality of its electronic circuitry, electronic components, or case work. It includes gold plated circuit boards, and high quality internal silver wiring all designed to give long life and the ultimate musical performance.

It is always exciting when a new project reaches the performance stage and the FBA-800 amplifier through its development has continued to astound and excite through thousands of hours of tuning and development.


Inputs – Stereo line level, stereo balanced.

Outputs – Stereo pair multi way locking binding posts.

Front panel gain selector – 6dB input attenuation.

Front Panel input selector – RCA or XLR.


Input sensitivity – 735mV for full output.

Power output – 40 Watts into 8 ohms both channels working.

Frequency response – 0dB 20Hz – 80kHz.

Bandwidth – 3dB points 6Hz – 113kHz.

Signal to noise – >96dB.

Distortion at 1 Watt,1 kHz – >0.05%.

Net weight – 25kgs.

Dimensions – 206 x 430 x 460mm (hwd).

Recommended Retail Price – AUD$12,750.00.

E. & O. E.