bellow - For a person or animal to emit a deep loud shout or roar, usually in pain or anger.
When Joan entered the office an hour late the third time this week, her manager Mr. Fass bellowed that if she wanted to keep her job, she should consider coming on time from now on.
tremor - A slight shaking movement, such as one caused by an earthquake or instability; also a subtle or faint sign of emotion, such as fear or excitement in the voice or body.
Because he was nervous, his voice had a significant tremor during the presentation.