16th- and 17th-century quotes on improvising

“What produces the wonderful effect, the particular charm, and the sweet sound of [improvised counterpoint] are the unexpected consecutive fifths and octaves, the sudden dissonant clashes among the voices, and other unusual liberties (stravaganze).”

Adriano Banchieri, Cartella musicale (Venice, 1614)
trans. Ernest T. Ferand

“When a well-trained singer came across a place especially suited for embellishing notes, he would not neglect to follow his inspiration, even when he knew that by his beautiful flourishes mistakes must occur.”

Silvestro Ganassi, Opera intitulata Fontegara (Venice, 1535)
trans. Murray C. Bradshaw

[in singing their improvised counterpoint] “these choirs come to represent those angelic voices which, continuously singing praises to the Lord, make in heaven wondrous choruses of harmony”…

Lodovico Zacconi, Prattica di musica seconda parte (Venice 1622)
trans. Prof. John Whenham

[…improvised counterpoint is…] “the most ingenious and sweetest composition that can be made.”

Giovanni d’Avella, Regole in musica… (Rome, 1657)
trans. Ernest T. Ferand

“It is pleasant to listen to the singing upon a plainchant in church if the group is well prepared, if all the voices make their proper clauses [passages]…and in each voice the right progressions are kept….[but]…it will be a difficult thing that no errors should occur, and not a few of them”.

Nicola Vicentino, L’Antica Musica Ridotta alla Moderna Prattica (Rome, 1555)
trans. Ernest T. Ferand