10" bass reflex subwoofer with DSP and 900 W RMS power. Flexibly expandable with the BOB-4 satellites for 2.1, 4.1, and 8.1 operation. DSP-controlled Class D amplifier (300 W + 2 x 300 W). Integrated Bluetooth audio streaming for wireless music enjoyment. Four EQ presets with status indicators. Signal limiter and crossover. Signal inputs via combo jacks (XLR/jack) and RCA. XLR parallel outputs for coupling further BOB systems or active speakers. Volume for subwoofer and satellites L/R separately adjustable. Stereo mono switching. Phase reversal switch. Fault, limit, signal, and power indicators. Integrated protection circuits: soft start, short circuit, limiter, overvoltage, overheating. Two M20 metal flanges for mounting the satellites. MDF cabinet with durable textured finish and metal grille. Built-in carrying handles and light weight for easy transport. Stackable due to recesses when placed horizontally. Delivery includes two speaker cables. Power supply: built-in IEC power supply with protective contact cable included. DSP: digital signal processor. Control: Bluetooth.