At the end of the 16th century, the changed social function of the madrigal contributed to its development into new forms of music. Since its invention, the madrigal had two roles: (i) a private entertainment for small groups of skilled, amateur singers and musicians; and (ii) a supplement to ceremonial performances of music for the public. The amateur entertainment function made the madrigal famous, yet professional singers replaced amateur singers when madrigalists composed music of greater range and dramatic force that was more difficult to sing, because the expressed sentiments required soloist singers of great range, rather than an ensemble of singers with mid-range voices.