Class D digital power unit with four independent 240 W amplifiers integrated into the same 19 ”rack chassis (1 u). It incorporates four balanced inputs with connections through removable strip, four speaker outputs for 100 V / 8 Ω line, independent volume control and high pass filter (HPF) for each of the inputs. It has protection circuits against peaks, short circuits, overheating and overload, and LED indicators for power, signal, peak and protection. 110 ~ 230 V AC power supply and cooling by two fans. SNR > 80 dB, THD <0.1%, consumption 1,200 W and weight 6.8 kg. Frequency response 20 ~ 20,000 Hz (70 ~ 20,000 with active HPF).