Use "ruffer" in a sentence

1. The gruff voice was gruffer than ever, as the old gentleman said abruptly, after the dreadful pause, "So you're not afraid of me, hey?"

2. Laurence's gruff voice sounded gruffer than ever, as Jo tapped at his door

3. “Officer Goody Two-Shoes can’t face the past,” he said in a gruffer voice

4. The corporal’s voice was gruffer even than usual