Driver:2.5″ x 8 excellent full range speaker Frequency Response: 100Hz-20,000Hz Sensitivity(1m,1W): 90dB Speaker Dimensions: 688x105x95mm(HxWxD) Material: Aluminum Impendance: 8 Ohms Transformer:20w-10w-5w-2.5w-8Ω(100Vor 70V)