Pat,
My music computer is packed away for this evening so can't be specific but BIAB has a built in utility to do just what you're after. It does require songs with melodies I think. You enter your range or maybe sing your range. i'm just guessing now so I'll stop. Check it out.
For me I have a very narrow range yet I do songs in all keys. It all depends on were the melody line takes you. Some songs I can't do in any key. It's mostly trial & error for me.


John
ESI Gigaport HD+
Lenovo Turion II /4 Gig Ram/ Win7x64 be
15.6" Monitor
"The only Band is a Real Band"
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