Усилители мощности стерео — Rotel RB-1582 MkII

The Rotel RB-1582 MkII is a Class AB stereo amp. Rotel builds each channel as a separate monoblock circuit inside one 3U case and offers the amplifier in silver or black, with balanced and unbalanced inputs.

Key specs that matter

It is rated at 200 W per channel into 8 ohm and 323 W into 4 ohm. THD stays under 0.03% between 20 Hz and 20 kHz, and intermodulation distortion is also below 0.03%. The frequency response spans 10 Hz to 100 kHz within 0.5 dB. Signal to noise ratio is 116 dB, IHF A weighted, while Rotel quotes a damping factor of 800. Gain is 26.5 dB through RCA and 22.5 dB through XLR. Input sensitivity for full output is 1.9 V on the RCA sockets and 3.0 V on the XLR sockets, with input impedance of 12 kOhm and 100 kOhm respectively. The case measures 431 x 144 x 407 mm, the front panel is 132.6 mm tall, and the weight is 17.6 kg.

Engineering and use context

The power supply rests on a very large toroidal transformer and 60,000 uF of reservoir capacitance, using slit foil capacitors that Rotel selected for fast charge and discharge. Grounding follows a star pattern on a copper plate. The output stage is fully discrete and uses 10 high current bipolar transistors per channel. Mains consumption is 550 W at full output, 60 W at idle and 0.5 W in standby, and the thermal output reaches 1104 BTU/h at 1/8 power. The North American version runs on 120 V at 60 Hz. A rear toggle switch selects manual power operation or automatic switching by a 12 volt trigger, and the 3.5 mm trigger input accepts any AC or DC control signal from 3 to 30 V, while the matching output passes a 12 V signal on to further components whenever the input is active. Thermal and over-current protection circuits guard against faulty operating conditions and work independently of the audio signal. Rack ears are supplied, so the 3U chassis can be fitted into a standard equipment rack.

Pairing

Both XLR and RCA sockets are provided, so the RB-1582 MkII can take a balanced or an unbalanced preamplifier feed, and the published gain and sensitivity for each input type show how much drive the source needs. Its reserve into low loads covers low impedance loudspeakers, and with the trigger link it can power up together with the preamplifier.

Alternatives

The Rotel RB-1590 is a bigger Rotel stereo power amplifier, rated at 350 W per channel into 8 ohm and 648 W into 4 ohm with twin toroidal transformers.