HiFi Rose - RA180 Integrated Amplifier

RA180: A Comprehensive Overview

The RA180 boasts an advanced Class D amplifier design, capable of delivering an impressive 800W output. It employs Gallium Nitride FETs, ensuring a flawless and linear output. The amplifier comprises four independent modules, providing flexibility for Bridge Tied Loads or bi-amping configurations. With a frequency range spanning up to 100kHz, the RA180 offers exceptional sound quality. It features separate outputs for two sets of stereo speakers, ensuring a balanced and immersive listening experience.

The RA180 is equipped with a built-in moving magnet and moving coil phono stage, complemented by an adjustable EQ for precise control over the sound’s tonal characteristics. An active crossover is integrated to support Super Tweeter frequencies, enhancing the amplifier’s ability to deliver a wide range of frequencies. The tonally flat output design ensures a consistent and balanced sound, while bass and treble tone controls provide additional customization options.

The RA180 offers a bypass Power Amp mode, allowing users to switch between the amplifier’s power output and a separate power supply. Additionally, it features a high-efficiency power supply powered by Silicon Carbide FETs, contributing to its energy-saving capabilities. Dimmable VU meters provide real-time feedback on the amplifier’s performance, enabling users to monitor its output levels effectively.

The RA180’s design seamlessly blends retro aesthetics with cutting-edge technology, creating a visually appealing and futuristic integrated amplifier. Its illuminated meters, sleek silver chassis, and gleaming sliders and switches exude a timeless elegance, while its wide frequency response and advanced features elevate the listening experience to new heights.

Each channel of the RA180 amplifier is equipped with two specialized AMP modules. One module is designed for stable bass and balance, while the other module is tailored for soft treble and super tweeter areas. Each AMP module supports 200W (8 Ohms) and can output up to 400W per channel, resulting in a total output of 800 watts. The amplifier features two independent modules that divide the high and low frequencies, respectively. This design ensures that the speaker receives a driving force that is increased without being affected by the back electromotive force, even when connected to a Bi-Amp. Additionally, the RA180 incorporates BTL Mode, which combines the output of the two independent modules to produce a thicker and more balanced sound.

The RA180 is phono-ready, featuring built-in moving-magnet (MM) and moving-coil (MC) phono stages with switch selection. It also offers adjustable EQ, with EQ values corresponding to curves from various record manufacturers, utilizing parts with a 0.1% tolerance.

As seasoned audiophiles are aware, amplifier design has undergone significant transformations, evolving from Class A to Class A/B and finally to Class D. Engineers developed Class A/B to address the high heat generation and low efficiency inherent in Class A amplifiers. Class D amplifiers boast higher efficiency and output compared to Class A/B, significantly enhancing the signal-to-noise ratio and total harmonic distortion (THD) characteristics, surpassing those of Class A and Class A/B. However, many audiophiles found the sound quality inferior to Class A and Class A/B due to the limitations of the digital circuitry.

In response to these challenges, HiFi Rose has developed the Gallium Nitride (GaN) Advanced Class D amplifier. This innovative product addresses key issues associated with existing Class D technology by employing cutting-edge materials. Class D amplifiers inherently possess a topology that theoretically delivers a perfect linear output at zero distortion and maximum power efficiency. Achieving this requires exceptional speed and accuracy in the switching action. However, previous Class D products struggled to match the linearity of Class A and Class A/B due to the limitations of Silicon FET, which couldn’t produce ultra-smooth and natural sound.

To overcome this limitation, HiFi Rose introduced the RA180 amplifier, which employs a new material, GaN FET (instead of Silicon FET), to address the issue. The dead time was dramatically reduced, resulting in a nearly perfect linear output with a switching speed approaching zero. This linearity surpasses the inherent limits of Class D amplifiers, producing a smooth and natural sound reminiscent of an analog amplifier.

Furthermore, the Treble Design of the RA180 amplifier extends even to the super tweeter area, ensuring exceptional clarity and detail in the treble range.

The human hearing range is known to have an upper limit of 15 to 20 kHz. So, why would it be necessary to build an amplifier with a higher range? Using modern research and experience, it’s now perhaps a good time to question this belief. Temporary high treble can extend well beyond 20 kHz. For instance, the trumpet has a frequency response that expands up to 100 kHz. The RA180 amplifier has an output range of 20 Hz to 50 kHz, 100 kHz at -3 dB, and 200 kHz at -6 dB. The frequency response range is designed to be wide so that high-resolution sound sources are not filtered. This ability might be beyond human audible range, but at a wide frequency, it faithfully plays the area. The depth and width of the sound and the realism will contribute to the expression.

The power supply that has been exclusively developed for the RA180 amplifier applies fourth-generation Silicon Carbide (SiC) FET technology to provide high output with less heat. Additionally, by using a self-developed PFC (power factor circuit), it is designed to be unaffected by sudden load fluctuations. The power supply device was developed to support a powerful damping factor, and the high output of 1,000 watts is designed to produce deep bass and accurate treble tones.

Specifications:

* Size: 16.9” W x 13.7” D x 4.3” H

* Weight: 36.8 lbs

* Finish: High Purity Aluminium

Inputs & Outputs:

* Audio input: Balanced XLR Line Input x1, Unbalanced RCA Line Input x 3, MM/MC (switchable) Phono Input x 1, COAX x 1, USB Audio In x1

* Audio output: Subwoofer Out x 1  

Power:

- FTC Power Output Rating (RMS): 200W x 2 channels (8 ohms, 20 Hz-20 kHz, THD 0.1%)

- Total Harmonic Distortion (THD): 0.05% (8 ohms, 1 W to 250 W, 1 kHz)

- Frequency Range: 10 Hz~100 kHz (8 ohms, 1 W)

- Load Impedance: 8 ohms

- Damping Factor: Speaker and H/F Speaker Output >150

- Signal to Noise Ratio (S/N): BTL / Balanced, Unbalanced / Phono MM, MC: 107 dB / 105 dB / 80 dB (MM), 60 dB (MC)

- Impedance Output: Speaker Output: 53 mOhms

- Subsonic Filter with On/Off Switch: -3 dB at 50 Hz

- Tone Control with On/Off Switch: Bass (100 Hz) / Treble (10 kHz): ±15 dB

- X-Over with On/Off Switch: HPF (-3 dB) at 600 Hz - 6 kHz

- Phono:

  - Turnover: Flat

  - Turnover at 300 Hz: (+7.7 dB at 100 Hz)

  - Turnover at 400 Hz: (+11.7 dB at 100 Hz)

  - Turnover at 500 Hz: (+13 dB at 100 Hz)

  - Turnover at 700 Hz: (+14.5 dB at 100 Hz)

  - Roll-Off: Flat

  - Roll-Off at 1.6 kHz: (-16 dB at 10 kHz)

  - Roll-Off at 2.1 kHz: (-13.7 dB at 10 kHz)

  - Roll-Off at 3.18 kHz: (-11 dB at 10 kHz)

  - Roll-Off at 3.4 kHz: (-8 dB at 10 kHz)

  - Roll-Off at 6.36 kHz: (-5 dB at 10 kHz)

- Power: SMPS (800 W)

- Voltage: AC 100-230 V, 50 / 60 Hz

- Audio In / Out on Rear: Trigger (Trigger Voltage can be turned on: 3.3 V - 12 V)

- Remote Control: IR Input (38 kHz Infrared Ray, within 10 m of operating distance)