In the 1720s and 1730s, at the height of the craze for these voices, it has been estimated that upwards of 4,000 boys were castrated annually in the service of art.
[12] Many came from poor homes and were castrated by their parents in the hope that their child might be successful and lift them from poverty (this was the case with
Senesino). There are, though, records of some young boys asking to be operated on to preserve their voices (e.g.
Caffarelli, who was from a wealthy family: his grandmother gave him the income from two vineyards to pay for his studies
[13]). Caffarelli was also typical of many castrati in being famous for tantrums on and off-stage, and for amorous adventures with noble ladies.
[14] Some, as described by Casanova, preferred gentlemen (noble or otherwise).
[15] Only a small percentage of boys castrated to preserve their voices had successful careers on the operatic stage; the better "also-rans" sang in cathedral or church choirs, but because of their marked appearance and the ban on their marrying, there was little room for them in society outside a musical context.
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