Descriptions:  Note:This is DIY Kits, you need do it yourself   Transformer Recommended Voltage: DC12-18V, the battery can also be, positive and negative automatic identification, do not worry reversed. Many of our family router power idle most of them can be used, the current size of the power output, 1A is the most basic requirement, 2A is more than a good, casual use of other power supply specifications may cause burn.    The Speaker Recommended: The main channel 10W+10W 3-5inch 4-8Ohm 10-20W Full_range or Bass speaker.  Subwoofer 20W 4-6inch 4-8Ohm 10-40W inch subwoofer Speaker.    if the speaker power is small, reduce the volume use; this bass amplifier to strengthen the design, so the volume is not necessarily the greatest use, whether an individual speakers may cause distortion. Be sure to use low-frequency subwoofer speaker speaker identification method is big magnet ring off stiff and strong_box seal, conditional use labyrinth box, paste sound-absorbing cotton, pure bass is relatively strong_.     Package included:  1 x Single Power Supply PC Subwoofer Mega Bass 2.1 Amplifier Board DIY Kit