HiFi Rose RA180

Each channel of the RA180 amplifier is equipped with an AMP module specialized for stable bass and balance and a module specialized for soft treble and super tweeter area, with two modules. Each AMP module supports 200W (8 Ohms) and can output up to 400W per channel, for a total output of 800 watts. There are two independent modules that divide the high and low frequencies respectively, so that the speaker and, when connected, Bi-Amping has a driving force which is increased without being affected by the back electromotive force. RA180 also features BTL Mode which combines the output of two independent modules to produce a thicker and more balanced sound.

Phono Ready

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

As longtime audiophiles know, amplifier design has evolved, from Class A to Class A/B to Class D. Engineers developed Class A/B to improve the high heat generation and low efficiency of Class A. Class D has higher efficiency and higher output than Class A/B, and it significantly improved the signal-to-noise ratio and THD (total harmonic distortion) characteristics, as compared to Class A and Class A/B. However, many found the sound quality to be inferior to A and A/B due to the limitations of the digital circuit. The Gallium Nitride (GaN) Advanced Class D amplifier developed by HiFi Rose has dramatically improved issues related to existing Class D technology; this was achieved by applying innovative new materials. Class D amplifiers have a topology that theoretically provides a perfect linear output at 0% distortion and 100% power efficiency. In order to achieve this, the switching action requires high speed and accuracy. However, previous products were weak compared to Class A and A/B in the linearity aspect, due to the limitations of Silicon FET, which couldn't produce ultra-smooth and natural sound. In the RA180, HiFi Rose has used a new material, GaN FET (instead of Silicon FET), to solve this problem. The dead time was dramatically improved, and a nearly perfect linear output was realized with a switching speed close to zero. This linearity goes beyond the Class D limits and produces a smooth and natural sound— like an analog amplifier.

The human hearing range is known to have an upper limit of 15 - 20KHz. So why would it be necessary to build an amp 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 20KHz. For example, the trumpet has a frequency response that expands up to 100KHz. RA180 has an output range of 20Hz - 50Khz, 100Khz@-3dB, 200KHz @-6dB. 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.

Balanced Power Supply

The power supply that has been exclusively developed for the RA180 applies fourth-generation Silicon Carbide (SiC) FET technology to provide high output with less heat. In addition, by using a self-developed PFC (power factor circuit), it is designed to not be affected 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.