AceShowbiz -

Robert Plant recently visited "The Tonight Show Starring Jimmy Fallon" to promote his new album, "lullaby and... The Ceaseless Roar". During a chat, the show's host Jimmy Fallon asked the Led Zeppelin vocalist to record a doo-wop version of Gene Chandler's classic called "Duke of Earl" with him using the iPad app Loopy.

Fallon handed Plant a microphone and the veteran rocker made a joke about it. As the British musician held the microphone, he told the funnyman, "This looks like one of them funny shops in Amsterdam!"

Fallon then began explaining how the app works and started the performance. He and Plant took turns singing lead. At some point, The Roots joined them to add some extra background harmonies.

Plant's "lullaby and... The Ceaseless Roar" debuted at No. 10 on Billboard 200 after being released earlier this month. During his visit to the show, he also took the stage with his band, the Sensational Space Shifters, to perform "Rainbow" and "Turn It Up" which both appear on the new LP.

The iPad app Loopy was previously used by Fallon to sing a doo-wop duet with Billy Joel. When the singer visited the same late-night show back in March, the host asked him to sing The Tokens' "The Lion Sleeps Tonight".