Miles elaborates this comparison in Our Southern Birds:

In song and movement the Thrasher is very like the Mocking Bird and Catbird, to whom he is closely related; but he is more of a ground bird than they darting in and out of brier patches and fence-rows, looking all over the yard and garden for cutworms and grubworms, mounting to a treetop only when ready to pour himself out in song. And what a song! In tone and delivery it resembles that of the Catbird, but is rounder and more uniformly sweet, containing no harsh notes and no imitations. Among writers on birds there seems a difference of opinion as to his quality as a musician, some pronouncing his performance second only to that of a Mocking Bird, and others declaring it to be a monotonous repetition of a single phrase. Well, it if be monotonous, then the Nightingale's is monotonous. All agree, I believe, in praising the sweetness of the Thrasher's tone. (123)