Power amplifier 2 channel class D 1U rack - JB SYSTEMS BEG-B08129

The JB Systems AMP 400.2 Mk2 is a professional 2-channel class-D amplifier delivering 2 x 250 W RMS at 8 ohms or 2 x 450 W RMS at 4 ohms. In stereo operation, the two channels remain independent. Mono operation links the inputs internally and produces a mono output, so the LEFT input alone can feed both output channels with the same signal. Bridge operation combines the final stages and provides 900 W at 8 ohms.

The Mark II design retains the compact rack format, with a standard 19" width and a 1 U height of 44 mm. Its internal layout has been redesigned to improve reliability and heat removal, while three fans help keep the operating temperature controlled. Power is supplied by a highly efficient soft-start switching power supply. A peak limiter helps prevent signal distortion, and the low-cut filter removes low frequencies at 75 Hz using a steep 24 dB/oct slope.

Input sensitivity can be selected as 0.775 V, 1.0 V or 1.44 V, allowing the amplifier to match different sources. A rear switch provides floating ground operation. To stop unauthorised users from changing the input levels, the supplied plastic cover can be fitted over the front controls with 4 screws. Audio inputs are balanced 3-pin XLR connections. A link output is available for daisy-chaining another power amplifier, while the loudspeaker outputs use speakON connectors. Protection is provided against short circuits, excessive temperature and overload.

The unit has an IEC power input rated at 240 V AC, 50 Hz, weighs 4.5 kg and measures 48.3 x 24 x 4.4 cm. Its colour is black; there is no display and no energy label. It is designed for 19" rack mounting with a 1U fixing height, and its IP rating is specified for indoor use. The frequency range is 20 Hz to 20,000 Hz, with a signal-to-noise ratio above 100 dB. The 2 channels deliver 450 W RMS per channel at 4 ohms in stereo, 250 W RMS per channel at 8 ohms in stereo, and 900 W RMS at 8 ohms in bridge mode. Listed functions are bridge mode and limiter.