Upon entering orbit of the Qomar homeworld, Prelate Koru requested to hear The Doctor's singing. CaptainJaneway suggested a concert be held aboard Voyager. At the concert, Prelate Koru, like all of the Qomar, was particularly impressed with The Doctor's singing. However, he was not fond of Harry Kim and the Kimtones' music, until The Doctor started singing as well.
Soon after, he arranged for Tincoo to arrange for The Doctor to perform in front of hundreds of Qomar, and to be transmitted to hundreds of millions. (VOY: "Virtuoso")