The Rotel RB-870 BX is a power amplifier that was manufactured from 1987 to 1991, designed in England and produced in the Far East. The amplifier features a sleek black finish and is built to deliver high-quality audio performance. With a power consumption rating of 500 watts, it demonstrates efficiency while providing robust amplification. The RB-870 BX measures 430 x 109 x 315 mm (WxHxD) and weighs approximately 9.4 kg. It was initially priced around 1,050 DM in 1992. The amplifier has a single input with a voltage of 1.0V and an impedance of 25 kOhm, along with one pair of speaker output terminals.
In terms of technical specifications, the RB-870 BX delivers continuous power output of 2 x 100 watts RMS at 8 ohms across the frequency range of 20 Hz to 20 kHz with a distortion factor of 0.03%. At 4 ohms, it can produce 2 x 200 watts at a frequency of 1 kHz with a distortion factor of 1%. The peak current capability is rated at 50A, and the amplifier features a considerable attenuation factor of 180 in the 20 to 20,000 Hz range for 8-ohm loads. The frequency response extends from 4 Hz to 100,000 Hz with a tolerance of +0.5/-3 dB. Additionally, it offers an impressive signal-to-noise ratio of 110 dB (IHF, A network).
The RB-870 BX is built with selected close tolerance components, a high power toroidal transformer, and direct signal routing, ensuring that it can handle low impedance loads efficiently and drive challenging speakers without issues. In mono bridge connection, the amplifier can output a channel power of 300 watts, highlighting its strength in performance. Other models in the same series include the Rotel RC-850 and RC-870 BX preamplifiers and the RB-850 and RB-890 power amplifiers.
