ROSE RA280

HiFi ROSE RA280 – High-End Integrated Amplifier with Class AD GaN Technology

HiFi ROSE RA280 is a high-end integrated amplifier that brings together innovative amplification technology, substantial power reserves and an exceptionally clean, sophisticated design. Developed as an evolution of the technologies introduced with the RA180, the RA280 uses HiFi ROSE's proprietary Class AD GaN amplification architecture to deliver a natural, transparent and highly controlled sound.

Its two completely independent mono amplifier modules can deliver 250 W per channel at both 4 and 8 ohms, for a total stereo output of 500 W. This architecture, combined with a damping factor greater than 250 and an output impedance of only 30 mΩ, provides precise control over the loudspeakers and excellent dynamic performance.

Next-Generation Class AD GaN Amplification

The heart of the RA280 is its innovative Class AD amplification technology with GaN FET transistors. HiFi ROSE developed this architecture to address some of the limitations traditionally associated with conventional Class D amplification.

The use of Gallium Nitride semiconductor technology enables extremely fast switching and a very short dead time, contributing to exceptional linearity and precise signal reproduction.

The result is an amplifier designed to combine the efficiency and power of switching amplification with a natural and refined sonic presentation.

Two Completely Independent Mono Amplifier Modules

The RA280 features two completely separate amplifier modules, each operating as an independent mono amplifier for the left and right channels.

Each module is capable of delivering 250 W at 4 ohms and 250 W at 8 ohms, providing a total stereo output of 500 W.

This dual-mono architecture helps minimise interaction between the two channels and maintains excellent stability even during demanding musical passages.

Two-Stage Analogue LC Filter

HiFi ROSE has developed a dedicated two-stage analogue LC filter for the RA280. Its purpose is to significantly reduce the residual carrier noise generated by the switching process inherent to Class D and Class AD amplification.

The filter maintains a very wide frequency response, with approximately -1 dB attenuation up to 65 kHz and approximately -3 dB at 85 kHz.

This design contributes to cleaner reproduction, improved spatial definition and greater resolution while preserving the natural character of the music.

Exceptional Loudspeaker Control

With a damping factor greater than 250 and an output impedance of only 30 mΩ, the RA280 is designed to provide precise control over connected loudspeakers.

This high level of electrical control helps the amplifier manage demanding loads effectively, contributing to articulate bass, excellent transient response and strong dynamic precision.

Extended Frequency Response

The RA280 offers an exceptionally wide frequency response, extending from 10 Hz to 85 kHz at 1 W into 8 ohms.

At full rated output, the declared bandwidth extends from 12 Hz to 83 kHz, allowing the amplifier to preserve a broad range of harmonic information from high-resolution recordings.

Analogue Bass and Treble Controls

The RA280 features dedicated analogue tone controls designed to provide practical adjustment without compromising the quality of the signal path.

• Bass: 100 Hz, ±15 dB.
• Treble: 10 kHz, ±15 dB.

The tone-control circuit uses an active high-fidelity equaliser based on an OP-AMP, with a 12 dB slope. The controls can be switched off when a linear response and the most direct signal path are preferred.

Integrated MM Phono Stage

The RA280 incorporates an MM phono stage, allowing a turntable equipped with a Moving Magnet cartridge to be connected directly without requiring a separate phono preamplifier.

The phono section provides dedicated Turnover and Roll-Off adjustments, including Flat and RIAA settings, allowing the analogue source to be integrated flexibly into the system.

High-Efficiency Power Supply

HiFi ROSE developed a dedicated 500 W switching power supply for the RA280, designed to provide stable power while keeping efficiency high and heat generation low.

The power supply uses silicon carbide FETs instead of conventional silicon FETs. This technology is capable of handling high voltages and temperatures while reducing power losses and heat generation.

The amplifier also incorporates a proprietary 2.5 kW Power Factor Correction circuit and a high-capacity capacitor, helping maintain stable performance during rapid load variations.

Premium Construction and Minimalist Design

The RA280 adopts a more streamlined aesthetic than the RA180 while retaining the distinctive construction quality of HiFi ROSE.

The chassis is manufactured from high-purity aluminium, providing excellent mechanical rigidity as well as effective thermal dissipation and shielding.

The amplifier measures 430 × 350 × 110 mm, increasing to 430 × 391 × 130 mm including the feet, and weighs 16.7 kg.

Key Features

• High-end integrated amplifier.
• Proprietary Class AD amplification architecture.
• GaN FET transistors.
• Two completely independent mono amplifier modules.
• 250 W × 2 channels at 4 ohms.
• 250 W × 2 channels at 8 ohms.
• 500 W total stereo output.
• Two-stage analogue LC filter.
• Frequency response up to 85 kHz.
• 12 Hz – 83 kHz bandwidth at full rated output.
• Damping factor >250.
• 30 mΩ output impedance.
• ±15 dB Bass and Treble controls.
• Bass control centred at 100 Hz.
• Treble control centred at 10 kHz.
• Integrated MM phono stage.
• Phono Turnover settings: Flat / 500 Hz / RIAA.
• Phono Roll-Off settings: 2.1 kHz / RIAA.
• Balanced input.
• 3 RCA line inputs.
• 500 W SMPS power supply.
• Silicon carbide FETs in the power supply.
• Proprietary 2.5 kW PFC circuit.
• 600 W maximum power consumption.
• 3.3 – 12 V Trigger input.
• IR remote control input.
• IR remote control included.
• High-purity aluminium chassis.
• Black and Silver finishes.

Why Choose the HiFi ROSE RA280

HiFi ROSE RA280 is designed for listeners who want a powerful and technologically advanced integrated amplifier without giving up the functionality of a genuine analogue Hi-Fi component.

The combination of 250 W per channel, Class AD GaN amplification, two independent mono modules, a two-stage analogue filter and a damping factor greater than 250 provides a particularly capable platform for driving demanding loudspeakers.

The integrated MM phono stage, adjustable tone controls, balanced input and three RCA line inputs make the RA280 a highly versatile solution for both digital and analogue Hi-Fi systems.

The result is an amplifier that combines power, efficiency, precision, wide bandwidth and sophisticated analogue circuitry in an elegant and relatively compact chassis.

Technical Specifications