Let's not forget that they sell auto-tune like units for singers now. He can surely use one of those live. That would fix a lot of his problems, and could even add some backing vocals when he wants them.
A singer in one of my bands has this thing:
http://www.amazon.com/Electronics-V...1-catcorr&keywords=tc+helicon+voicelive+touch
A singer in one of my bands has this thing:
http://www.amazon.com/Electronics-V...1-catcorr&keywords=tc+helicon+voicelive+touch
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