QUOTE(Mezzo1974 @ Sep 18 2009, 06:09 PM)

Yes, they can, but it should be a choir of trained voices.
The case is different if you try to put a trained voice in an amateur choir - usually not a good idea. The trained voice might be able to blend in, but it will literally strangle itself because of holding back too much.
I agree with you Mezzo...it is very hard for a well-trained voice to come *right* back to nothing when singing with people with, say, no support. I have found in the past that it is almost impossible to blend with people because they are so unbelievably quiet (to the point of not being well heard over other parts.) You also feel you are marking all the time, which is quite weird when singing Bruckner or something! In that situation, however, any conductor worth their salt should be able to help less experienced singers use their voices better so everyone can meet in the middle.
As for church choirs, my choir is very elderly, so a young trained voice would stick out like a sore thumb by simply singing one steady note!!!! (But they are lovely and enthusiastic

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