METALLICA drummer Lars Ulrich joined his father, 86-year-old Danish musician, filmmaker and former tennis pro Torben Ulrich, on stage this past Sunday, October 26 at HAUT i Huset i Magstræde in Copenhagen, Denmark for an improvised set of experimental music as part of this year's Wundergrund festival. They were joined during the performance — which was witnessed by around 150 people — by pianist, composer and improviser Søren Kjærgaard and special guests Claus Bøje (drums) and Peter Friis Nielsen (bass).Check out a photo gallery at Gaffa.dk. More photos are available below. Torben Ulrich and Søren Kjærgaard have made three albums together: "Suddenly, Sound: 21 Songlines" (2009), "Alphabet, Peaceful, Diminished: 29 Proposals From The Towers Of Babble" (2010) and their latest release, "Meridiana: Lines Toward A Non-Local Alchemy", which came out last week via Escho. Torben Ulrich, who is said to be METALLICA's biggest fan and its biggest critic, famously told his son "I would delete that" when asked for an opinion of a new song during the writing sessions for what became 2003's "St. Anger" album — a scene immortalized in the "Some Kind Of Monster" documentary. Torben added, as Lars laughed uncomfortably. "For me, it doesn't cut it. It sounds like a guy shouting in some kind of echo chamber." Asked in a 2005 interview if he was disappointed that Lars didn't pursue tennis as a career, Torben said: "No, no. The main thing was that he do what he thought was his choice — not our choice. But in order for him to know that more clearly, we encouraged him to leave Denmark for a year and travel to Florida, to a place called the Nick Bollettieri Tennis Academy. He went there when he was 13 or 14. He was very interested in tennis at that time, but he was also very interested in music. After a year, he still wanted to go out and listen to the concerts and I think at the Academy they were not so keen that he stayed out, so he was reprimanded there for keeping some late hours." In a 1995 interview, Lars Ulrich, who will be 51 in December, stated about his childhood: "I grew up in as open an upbringing as you can imagine. Americans would call it spoiled. But I was very independent. I had nothing tying me down. At the same time, anything I wanted I had to get it myself. It's 1975, and I want to go see BLACK SABBATH. As far as my parents were concerned, I could go see BLACK SABBATH 12 times a day. But I had to find my own means, carrying the paper or whatever, to get the money to buy the tickets. And I had to find my own way to the concert and back. From that point of view, I was left alone a lot. But in terms of culture, there was always shit going on around the house. "My dad was always around music He was hanging out with Sonny Rollins, Don Cherry, Dexter Gordon. Dexter Gordon was my godfather. I used to play with Neneh Cherry when we were little kids. Her stepfather, Don Cherry, lived like six houses from where we lived in Copenhagen. Those types of people were always around. "Even though tennis was his main source of income, my dad was also writing about jazz in the papers in Copenhagen. Miles Davis and Ornette Coleman were always playing in the stereo around the house. Later it was THE DOORS and Jimi Hendrix."