The other day, I got to hear my cousin play through one of these. He was playing for a group of about 40 seniors.

https://www.sweetwater.com/store/detail/EON615--jbl-eon615-1000w-15-inch-powered-speaker


He uses a Casio PX160, mic for voice, and drum machine....volume was appropriate for the size of the group....and it had a big sound.


Gotta say, I was impressed.