Castrato
It is impossible now for us to know what these great castrato voices sounded like, but they must have had very powerful voices and many of the singers were very skilled in singing and adding musical ornamentation to the songs. In the 18th century Italian opera became very popular in England. This was largely due to the German-born composer Georg Friderich Händel who moved to England in 1709 and wrote lots of Italian operas. Many singers who sang in London came from Italy, and many were castrati. The most famous one was called Farinelli.