What do you consider to be not too far north? You don't have to go to the Boundary Waters Canoe Area Wilderness to hear and see Loons.
We spent the week before July 4th at Moose Lake State Park in Moose Lake MN.
While out fishing, we had a loon family (2 adults and 2 chicks) swimming within about 20 feet of our boat. They came toward us, not the other way around. We saw them each time we were out on the lake (Echo Lake) and we heard them a lot at night when we were in our campsite. And I'm sure that Loons are located in many other MN state park lakes, even some of those further south.