Stefan Brock Kozinski, 61, formerly of Chadds Ford, an internationally known composer, conductor and musician, died this month in his apartment in Bremen, Germany.

The German medical examiner said he was found unresponsive in his bed by a friend on Thursday, Dec. 11. The cause of death was a heart attack. The exact time of his death was unclear.

A native of Wilmington, Mr. Kozinski lived in many places throughout his music career - Chadds Ford, New York City, Spokane, Wash., and Germany. At the time of his death he had worked as solo coach of the Theater der Freien Hansestadt Bremen since August 2008.

He was a member of the faculty of the University of the Arts in Berlin in 2007 and 2008, was on the music staff of the Anhaltisches Theater Dessau from 2001 to 2007, and was a professor at the University of Music and Theater in Hannover, Germany.

"He was devoted to and passionate about his music," said sister-in-law Patti Allis Mengers. "It was his life."

A 1970 graduate of the Tower Hill School in Wilmington, Mr. Kozinski earned an undergraduate degree from Princeton University and a graduate degree from the Juilliard School of Music in New York City.

He began his piano studies at age 4 and was soon playing and composing for various instruments. Mr. Kozinski was 9 when he won the Philadelphia Orchestra's Children's Composition Contest with his Suite No. 1.

Mr. Kozinski created more than 60 arrangements for full orchestra, big band, and organ, as well as operatic reductions for small orchestras. He set to music five poems written by his brother, David P., for a song cycle entitled "Afterlife of Memory."

His reduced score for Daniel Catan's Il Postino premiered on the East Coast with Center City Opera at the Prince Music Theater in Philadelphia in May 2012.

He played keyboard and conducted the orchestra in his reduced score version of Humperdinck's Hansel und Gretel for the Delaware Dance Company.

His compositions have been performed by the U.S. Marine Band, New England Ragtime Ensemble, and Radio-Philharmonie Hannover, where his orchestrations of Civil War-era spirituals for the Harlem Spiritual Ensemble premiered in 1994.

"For a guy who was classically trained, he loved jazz, soul and ragtime," said Mengers. "He wasn't a prig."

His SymFunny concerts for children were performed in the United States and Canada. Mr. Kozinski's compositions, published by E.C. Schirmer and Margun Music, are part of the Moldenhauer Archives at the Library of Congress, and the Kozinski Archives.

Mr. Kozinski performed on organ and piano and conducted in venues around the world starting at age 13. He conducted the Wilmington Symphony, now the Delaware Symphony, playing his "Elegy for Orchestra." He also conducted Die Fledermaus, Madame Butterfly, and The Magic Flute for OperaDelaware. He also was music director of the New York International Tour of George Gershwin's Porgy and Bess from 1997 until 2006.

"I can't think of anyone who plays Gershwin's music more feelingly and more beautifully," said composer Gunther Schuller, a friend and supporter.

Mr. Kozinski was frequently featured as a piano soloist with the Boston Pops, and the New York City Ballet at Lincoln Center.

He played some of the grandest organs in the world, including the 10,100-pipe Aeolian organ at the Longwood Gardens Conservatory in Kennett Square, the 6,027-pipe Walcker Great Organ at Methuen Memorial Music Hall in Massachusetts, and, at 18, one of the organs at the Cathedral of Notre Dame in Paris.

Mr. Kozinski twice received the Dr. Eugene Szatkowski Award from the Americans of Polish Descent Cultural Society of Delaware for his musical achievements.

Surviving, besides his brother, are his former wife, Francena Chalfant, and his longtime companion, Daniela Kappel.

A memorial service will be held at 3 p.m. Sunday, Dec. 28, at Christ Church Christiana Hundred, 505 E. Buck Rd., Greenville, Del. Musicians may bring their instruments to play at the reception in the parish hall following the service. Burial will be private.

Contributions may be sent to the Kozinski Archives, 126 Ridge Rd., Chadds Ford, Pa. 19317.

bcook@phillynews.com

610-313-8102