Good question. You’ll hear it at all the settings if you’re in the room with it, and on the super setting - 100% - you’ll hear it at in the other room. I did get used to it and I’m fairly sensitive to sound.

The Mini 3 might be the best balance between a significant amount of heat and little noise. But even with that unit you can hear it in the room.

Also, I was able to sell this someone local.