Steve Schwartz replied to me:

>>I would doubt seriously, however, that in a blind experiment, I and many,
>>many others could not pick-out or distinguish an all-male boys choir from
>>an adult imitation.
>
>Your ears are way better than mine, in that case.

Apparently so.  And not only mine.  After posting the above statement last
week, I have casually asked five friends (four choir members and one choir
director) whether they would include themselves in the "many, many others"
above.  All immediately said yes.  (One considered the question a joke,
that is she thought I was joking.) Their consensus:  pre-pubescent male
choirs have a distinctive, unique, sound not reproducible by adults
regardless of training.  I'd like to hear other's opinion on this.

>Yes, mature voices sound different than young voices.  But choral singing
>isn't a matter of the individual voice, but a blend of voices.  That blend
>can be manipulated.

True.  But choral singing is a "blend" of voices resulting from individual
voices.  The blend can (and does) reflect the age of the individuals.  I'll
stick by my contention that a college-age "glee" club" sounds distinctive
from a more mature group of the same size and voice breakdown singing
the same music in the same "style".  A group of 21-23 year-olds sounds
different than a group of 20-50+ year-olds.  Again, I'd like to hear other
opinions on this as well.

Thanks,
David Pitzer