Singer and song-writer T-Pain sings without auto-tune for NPR's "Tiny Desk Concert" series, and he sounds great.

The Tallahassee, Florida, native has been in the spotlight for nearly a decade with his auto-tuned tracks. His single "I'm Sprung" from his debut album "Rappa Ternt Sanga" grabbed listeners with its robotic melody.

Ten years later, he appears on NPR's show with his pianist, Toro, to sing "Buy U a Drank" and other songs, acoustic style. T-Pain lets out his vocals to prove to the world that he indeed can sing.

He also sung, "Up Down (Do This All Day)," and "Drankin Patna," in front of a live audience. The 13-minute show was posted on NPR's website Wednesday.

Many people in the past said that T-Pain could not sing and thus has to rely on the electronic vocal effects of auto-tune. 

"This is weird. I've never done this before. I didn't think you guys would actually come," he said in the video. "I know you're wondering where the auto-tune is going to come from. I got it right here in my pocket. It's surgically inserted."

T-Pain is known for changing the sound of pop music. He collaborated on many hit songs during his career. Some collaborators included 'Lil Wayne, R. Kelly and Chris Brown.

The effect is common today and is still used in many songs by various rappers and singers.

During T-Pain's performance, he sang his first number one hit "Buy U a Drank" with ease. He ripped vocals for the second song "Up Down (Do This All Day)," getting into it more through the performance as he dances at some parts of the song.

He said, "I love this!" before going into his last song.

T-Pain showed that he can sing just as well as many of the top singers in the industry. It looks like Trey Songz and the rest of them have real competition after all.