... radio ,digital karaoke,with VFD display Specifications: With usb,sd card read function, play mp3 type music,can ... audio frequency with output.Output power: 30W+10W*2(RMS)Speaker driver: woofer 4 inch,satellite 3 inch ... *2 Frequency Response 55Hz-20KHzImpedance4ΩDistortion0.1%S/N: ≥ ... .comhttp://yinco-audio.en.alibaba.com D-113 2.1ch USB/SD multimedia speaker