The twelve concertos of L'Estro Armonico, Op. 3, by Antonio Vivaldi (1678-1741), created a huge sensation when they were published in Amsterdam in 1711, introducing Vivaldi’s energetic, dynamic, and flamboyant style to those northern Europeans who had not already encountered it from circulating manuscripts. Within a few years pirated editions appeared in London and Paris, and Vivaldi was the biggest of musical celebrities, with Bach and other composers studying and assimilating his style.

The Eleventh Concerto of the set caused the biggest stir of all, and 300 years later, its boldness is still remarkable. It begins with an introduction in short segments, as Corelli might have, but where Corelli would have settled in and gotten comfortable, Vivaldi begins in the thick of battle, with the two solo violins in a canonic feud in eighth notes, a vigorous episode for the solo cello and continuo, a brief recitative, and an aggressive fugue. The slow movement is in the rhythm of the siciliana, which was usually associated with pastoral moods, but here there is a decidedly non-pastoral tension. The combative mood of the last movement is much like that of the first. Music of such sustained intensity changed the way composers thought of instrumental music. The idea that the orchestra could rival the voice as a vehicle for important or profound music began to take hold.

Lawyer and lutenist Howard Posner also annotates programs for the Salzburg Festival.