While aboard, he was very unhappy with The Doctor, a "primitive holographic construct." He even suggested to Tincoo, an associate of his from their ship, that they try to reprogram him, and deactivate his vocal subroutines. However, his opinion of him changed when he heard The Doctor hum a song.
At the concert, Abarca and all the Qomar were amazed at The Doctor's singing. However, when "Harry Kim and the Kimtones" played, none of the Qomar were impressed. Prelate Koru whispered something to Abarca, and he yelled very loudly, "WE WISH TO HEAR THE DOCTOR.", at which point The Doctor took the stage and started singing. (VOY: "Virtuoso")