what part of MV should i be expected to sing in vibrato NATURALLY? i'm pretty sure the exercises "high-released vibrato", "crescendo-diminuendo" and other exercises after it are for refining the vibrato.. I'm on CD 2, the last exercise (edgy vibrato/co co co) and still haven't got my vibrato, the only improvement i made is i can force it out (this has nothing to do with pulling up chest voice, i never used it when i practice vibrato scales)..

so for those who used mastering vibrato, what exercise made your vibrato to come out NATURALLY? is it the fast twitch?