The earliest documents of his career show him already to be employed as the maestro di cappella, the choirmaster, at the cathedral of Ancona in 1575.
Most of his works were canzoni alla napolitana, canzonas in the Neapolitan style, a light form of villanella (with a rhyme scheme of a a b c c, but with the individual lines elaborated in the manner of the madrigal).
To say they sold well and established his fame is an understatement; reprints and new editions appeared throughout Europe, in places as distant as Nuremberg, Antwerp, and London (in 1588).
Ferretti's canzoni, along with the works of Orazio Vecchi, are considered to be the most important musical influence on the English madrigal style of Thomas Morley, which commenced in 1588 with the publication in England of Musica transalpina, a wildly popular collection of Italian madrigals fitted with English words.
One of them is a celebration of the naval victory at the Battle of Lepanto (October 7, 1571), and is a coarse, abusive taunt of Sultan Selim, written in the dialect of the Venetian mariners who defeated his fleet.