4.The PA speaker's Details: A: L18/6620 subwoofer 18 inch horn-loaded,push-pull designed subwoofer Frequency Response(±3dB)45-300 HzFrequency Range(-10dB)40-400 HzSensitivity (1W/1M)108 dBMax.SPL136dB continuous,142 dB peakNominal Impedance4ohmRMS Power Handling1200 WPeak Power Handling4500 WRecommended Amplifiers1000to1500 Watts into 8 ohmsEnclosure Dimension1100(W)x618(H)x752(D)mm/43.3(W)x24.3(H)x29.6(D)inch Shipping Dimension1145(W)x668(H)x797(D)mm/45.1(W)x26.3(H)x31.4(D)inch LF Transducer2xHiPower L18/6620Net Weight86.5kg(190.7 lb)Shipping Weight95.5kg(210.5 lb)