Classically trained singers sing using lots of vibrato, exaggerated diction etc. As I understand it they are seeking to produce a 'pure' musical sound - which takes a lot of arduous training to get right. In producing this particular sound these singers tend to move quite a long way from their natural speaking voices. Such singing is highly stylised and, hence, not to everyone's taste. Nevertheless, it is extremely skilful and can be very impressive in the context of a live concert (I will never forget hearing Cecelia Bartoli sing in the Albert Hall - spine-tingling stuff!).

Pop and Rock singers, on the other hand, are often concerned with producing a 'unique' sound which distinguishes them from an army of competitors. I caught a snatch of Elton John the other night on the TV - and I couldn't help noticing that he sings in a high, slightly 'strangled' way whilst adopting a peculiar mid-Atlantic accent. There are lots of other examples - but my Pop references are very out of date!

In contrast to these examples many traditional singers have singing voices which are very like their speaking voices - think of the Norfolk singers, Harry Cox and Sam Larner, for example. They were both old, East Anglian countrymen and when singing they were not trying to produce a stylised or unique sound - they sounded like themselves.

On the other hand there does appear to be a stylised, post-War Revival 'folk voice' - especially among male English singers - a rather nasal sound which is instantly recognisable.