The Cambridge History of English and American Literature in 18 Volumes (1907–21).
Volume VI. The Drama to 1642, Part Two.
§ 7. Causes of their success
The success of the companies of choir boys in both early and later times was, doubtless, due, in no small degree, to the songs scattered through their plays and the instrumental music before the play began and between the acts. Other companies, of course, had incidental songs, but, apparently, not so many of them, and instrumental music seems not to have been given in the public theatres. That it was a prominent feature of the performances given by the boys, notwithstanding Clifton’s declaration that his son and other boys taken up by Robinson Evans and Giles were “children noe way able or fitt for singing, nor by anie of the sayd confederates endevoured to be taught to sing,” we know from passages in several contemporary plays, as well as from the explicit statements of the duke of Stettin who visited Blackfriars on 18 September, 1602.