Glenn Miller's reign as the most popular bandleader in the U.S. came relatively late in his career and was relatively brief, lasting only about three and a half years, from the spring of 1939 to the fall of 1942. But during that period he utterly dominated popular music, and over time he has proven the most enduring figure of the swing era, with reissues of his recordings achieving gold record status 40 years after his death. Miller developed a distinctive sound in which a high-pitched clarinet carried the melody, doubled by a saxophone section playing an octave lower, and he used that sound to produce a series of hits that remain definitive examples of swing music. Miller's approach is not much appreciated by jazz fans, who prefer bands that allow for greater improvisation than was found in his highly disciplined, rigorously rehearsed unit. But he brought the swing style of popular music to a level of sophistication and commercial acceptance it had not previously achieved and would not see again after his untimely passing.