OMG, I love that "wail" sound - and yes, that I have heard before!
The wail is most frequently given in the evening or at night, and can be heard for many miles. This haunting call is not an alarm call but is used to keep in contact with other loons on the same lake and surrounding lakes.
It is a haunting sound. I love that!
That yodel sound is cool, too.
Man...what it must be like to live in a rural area and hear these things as they naturally occur.