be in poor voice

To sound grating or unpleasant, as of a singer or other vocal performer. Oh, we left the show early because their lead singer was really in poor voice. I love Alice, but you cannot let her sign up for the talent show—she loves to sing but is always in poor voice. A: "Did you hear the way that singer was screeching last night?" B: "Yeah, he was really in poor voice. I wonder if he was sick or something."

be in good, poor, etc. ˈvoice

be singing well, badly, etc: The soprano was in excellent voice.