Pro Home Karaoke System Using Powered Mixer

My parent love to sing. I remembered about 3 years ago they asked me to accompany them to pick the best home karaoke system. I picked the system just like what karaoke commercial did. They sound great and my parent was happy at that time. Until about a month ago, they asked me again to make some improvement on their home karaoke system. They wish to get more power and dynamic to play music even louder.