Sunlightsquare is a pseudonym of British Italian music producer, pianist and digital entrepreneur Claudio Passavanti also known as Doctor Mix on YouTube. Primarily known for his work in Latin music, jazz fusion and house music, he performs live at festivals and clubs worldwide. He has collaborated with international artists, most notably with American drummer Steve Gadd and bassist Will Lee. As a YouTuber, he reviews synthesizers and explains synth-pop songs.