I have an old set of audio-technica speakers that don't require batteries. They were wonderful, so I bought these for my daughter. When I got the, I opened it up and was angry when I saw the spot where the batteries were supposed to go. I wanted speakers that didn't use batteries. But, my daughter later on showed me that the speakers work both with, and without, batteries. It's very nice. Without batteries, the sound is loud enough for any single listener. With the speakers, they get really loud. Really loud. Good enough for an entire room full of people to hear very well.
I plan to buy another set of these for myself soon.