SPECIFICATION Mode DSP501 DSP503 DSP557 Full-range Speaker / HF Driver 4.5"x1 4.5"x1 6.5''X1,1''X1 Normal Power 3W 3W 10W Max Power 6W 6W 20W Line Voltage 70-100V 70-100V 70-100V Sensitivity(1m,1W) 91B 91dB 91dB Max.Sound Pressure Level(1m) 97dB 97dB 104dB Freq. Resp. 60-20,000Hz 60-20,000Hz 80-20,000Hz Hole for Mounting 154x164mm 154x162mm 190x275mm Dimensions(mm) 80x180 80x175 305x220 x110