Upon entering orbit of the Qomar homeworld, Prelate Koru requested to hear The Doctor's singing. Captain Janeway suggested a concert be held aboard the 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 in one of the lecture halls, and to be transmitted to hundreds of millions Qomar. (VOY: "Virtuoso")