I can't provide a resource, Jim. It is something I discovered while fighting with "God be with You 'til We Meet Again." That hymn has a range from G to B in the key of Gmaj and from C to E in Cmaj. While two notes above the octave might not sound like much, it is. A soprano, of course, could raise the octave and still harmonize.
In Cmaj, I reasoned, well, what if I dropped the key three notes to Gmaj, wouldn't that be enough to lower the top notes into my range? So I thought. I mean, after all, isn't that what singers are always on about, "their" key? As you might have guessed, it did not work. The issue is not the notes, it is the spread, the range. I set about experimenting using a Snark tuner.
That led to having a look at the song book. My lead sheets are a lot easier to scan than full scores. That's when I noticed a pattern: ranges of an octave plus minus one, two, maybe three notes.
In conjunction, watching church leaders, it suddenly occurred that the leaders were expecting the congregations to automatically sing in 12 keys. No wonder people have a time of it.
(As always, open to further learning.)

Last edited by edshaw; 12/29/18 03:56 PM.
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