[1] In rare cases an adult man may be able to sing in the soprano range using his normal or modal voice (high chest voice) and not falsetto due to endocrinological reasons, like Radu Marian, or as a result of a larynx that has not completely developed as is allegedly the case of Michael Maniaci.
[2] A sopranist is able to sing in the soprano vocal range which is approximately between C4 and C6, though at times may expand somewhat higher or lower.
This practice is most commonly found in the context of choral music in England.
There is a large body of music for the male soprano that was written when it was common to use a castrato – a voice type which, for all intents and purposes, no longer exists, as the practice of castrating trebles was abolished before the end of the 19th century.
An exception is Alfred Schnittke's 1995 opera Historia von D. Johann Fausten which calls for both a female alto and a male soprano Mephistopheles.