Hi Ms Camille

I just want to check whether I am distinguishing between vibrato and straight tone properly. I naturally sing in vibrato (I think), so when I try to "switch gears" to straight tone, I find that my voice becomes slightly more nasal, and that there is a little more tension in the throat. I even experience a tickling sensation in my throat. Is that normal? (Maybe it is because as I try to make my vocal folds vibrate less, the vibration is transferred to my throat, giving me a tickling sensation?)

Thank you

Good question, Kang! It sounds like straight tone is causing a bit of undue stress. I encourage you to sing with vibrato, then notice if there's a second or two of "straight tone" naturally occuring before your vibrato "rings" at the end of a note or phrase. For most singers, that's the case. Then, see if you can sustain that "straight tone" for a little longer, before finishing the note or phrase with vibrato. 

Hope that helps!