I bought this to amplify music on my cell phone. It does a fantastic job! Takes 4 AA batteries or plugs into a computer slot for power. I am looking through my pile of old AC adapters to try plugging into this next. The speakers fold up for extreme portability. The volume is adjustable and loud enough to match the sound level one hears when wearing headphones. Sure beats the dinky speaker on my LG K7 phone! Shop around before buying. I've seen prices vary from $10 to $50.