The crucial differences with the previous wave can be seen in the downward shift in melodies, increasing durations of movements, the acceptance of Mozart and Haydn as paradigmatic, the greater use of keyboard resources, the shift from "vocal" writing to "pianistic" writing, the growing pull of the minor and of modal ambiguity, and the increasing importance of varying accompanying figures to bring "texture" forward as an element in music. In short, the late Classical was seeking music that was internally more complex. The growth of concert societies and amateur orchestras, marking the importance of music as part of middle-class life, contributed to a booming market for pianos, piano music, and virtuosi to serve as exemplars. Hummel, Beethoven, and Clementi were all renowned for their improvising.