My voice sounds quite deep and 'cultured/well spoken' in my head. Unfortunately having to transcribe a discussion I recorded the other day I was reminded I actually sound really droney and nasal and like the voice of someone playing a low-ranking pedantic jobsworth in a sitcom. 
I have a meeting tomorrow where I have to present some stuff so, following listening to the recording, I have written all over my notes to vary my cadence and tone - I'm sure... or I hope... I am more varied in normal conversation but I think I can get very monotone when checking notes.