The four Mills Brothers had a style that combined the best elements of vaudeville, Negro minstrelsy and the barbershop quartet with elements of the new jazz sound. Their habit of cupping their hands over their mouths to create an orchestral sound (similar to effects created by Europe's Comedy Harmonists), was a sensational factor in their success story, and appearances on popular radio programs like 'Rudy Vallee's Fleishmann's Yeast Hour' led to their first million-selling record, 'Tiger Rag/Nobody's Sweetheart' in 1931. The Brothers endeared themselves to movie audiences the world over with appearances on such hits as 'Big Broadcast of 1932' with Bing Crosby, Kate Smith, Cab Calloway and the Boswell Sisters.