>>24670976This whole vagueness is meaningless for conveying useful information. Technically I change my voice when talking to friends, or cowokers, or clients. But everyone can distinctly recognize it's the same voice. There must be a line drawn somewhere.
The easiest place to draw the line is vibrato. Wait for them to sing in the voice you deem 'fake'. Vibrato is naturally produced from holding long notes - it's more difficult not to produce vibrato than otherwise. It is similar to how your muscles tremble or shake when holding heavy loads. It's impossible to do pleasing, unforced vibrato in a fake voice.
Luna actually lampshades the issue in this old clip. Her baby voice is incapable of vibrato.
https://www.youtube.com/watch?v=aUIIKKVBjAw 
