I have a vague memory of reading somewhere that there are some eighteenth-century choral pieces that are more or less unsingable today, because they were composed specifically for castrati. According to this article or whatever it was, no singer today has the range (from baritone to soprano) or power (something to do with being barrel-chested?) to sing these pieces today, and if they are performed they have to be split up between male and female vocalists. True?
the topic came up in this thread, wherein Kimstu and Satan provided some useful links (along with a typical Satanesque outburst of ego).
One site linked by Commander Fortune mentions that to make a recording for a movie on a castrato, they elctronically merged two voices, as you suggested.
The poster formerly known as jti (sig™ inserted at request of dantheman).
It is much less an issue in choral music than in late Baroque / early Classical opera.
In choral literature, the effective range of the singer is much more important than the particular quality of the voice in question, and certainly more important than the gender – and other qualities – of the voice’s owner. The modern soprano, or boy soprano, fills this gap with no trouble at all.
But it was in opera that the castrato was in his element; the blend of the huge physical – and despite castration, very masculine [some of these guys were considered sexual idols] – stage presence and powerful soprano voice is nearly impossible to duplicate these days. Usually, castrato roles are sung by women in modern performances (Marilyn Horne made a career out of these parts); obviously they are equipped to meet the musical demands, but cannot present a plausibly male character.
Lately, castrato roles have been more often assigned to countertenors – men who sing in the typically female vocal range without any physical alteration (either by having an unusually high-placed voice, or through use of a carefully blended and strengthened falsetto). They bring a more realistic masculinity to the stage, but often lack the vocal brilliance of their female peers, and certainly of their surgically altered predecessors. But the best of them – notably David Daniels and some others – have managed to bring enough vocal prowess to the mix to present nicely rounded performances.
I’m afraid I’m going to have to flaunt my ignorance here, but how would a performer like the male lead in Phantom of the Opera compare to a castrato’s range and power? I say it flaunts my ignorance because that’s the handiest point of reference for me to grasp based on the music I’ve listened to so far.
You’re asking a question that’s pretty much impossible for a modern person to answer. The only recordings of a castrato (Alessandro Moreschi) aren’t useful for comparison because he was a really bad singer. His voice has a strange quality, but no real power or control. Descriptions of the great castrati lead me to believe that they had the power of today’s great basses and tenors, with a large range from baritone leading into the upper soprano.