Del sonare sopra ’l basso con tutti li stromenti e dell’uso loro nel conserto

Agostino Agazzari's treatise, Del sonare sopra ’l basso con tutti li stromenti e dell’uso loro nel conserto (1607), is an early guide to performing thoroughbass. This system of accompaniment, also known as basso continuo, was common in 17th and 18th-century music. It involved playing a written bass line with keyboard instruments, allowing the performer considerable freedom to improvise harmonies based on shorthand figures. Agazzari distinguished between "foundation" instruments like the organ and lute, and "ornament" instruments for melody. His work highlights the Baroque shift from the equal importance of voices in Renaissance music to the contrasted roles of melody and bass parts.123