He was born in 1945 as a son of the music teacher, pianist, and organist Alexander Kroll. He began to compose his first piano pieces at the age of eleven and from 1957 to 1959 wrote a Symphony in G minor for full orchestra. He studied in Rochester, New York, and German literature at Yale University, obtaining a doctorate in 1973 on the subject of the German writer Klaus Mann.
Since 1969, he has lived in Germany, where he has worked since 1976 on a six-volume biography of Klaus Mann. In 1974 he was active as a teacher at the Carl von Ossietzky High School in Hamburg - Poppenbuettel. In 1988 and 1989 he served as a training representative at the German seminar of the University of Freiburg in Breisgau. He has also lived and worked occasionally in Brazil.
- 1959 - Symphony in G Minor
- 1965 - The Scarlet Letter (opera in four acts, premiered 1981 in Cape Coral, Florida)
- 1966 - Lieder aus der Einsamkeit (Songs from the Loneliness), 1966, premiered 1982 in Wiesbaden
- 1969 - Romance in D minor for violin and piano
- 1969 - Frantumi song cycle
- 1970 - Kerzenglut (Candle-Glow) in D minor for violoncello and piano
- 1980 - White Nights (opera in three acts; unfinished)
Clay/tone carrier publications
- 1998 - The Scarlet Letter character (play and third act)
- 2001 - Lieder aus der Einsamkeit und andere Lieder (Songs from the Loneliness and other songs)
Series of publications on Klaus Mann (publisher and co-author), 6 vol., Wiesbaden, 1976, Hamburg, starting from 2002 (ISBN 3-88179-003-9, ISBN 3-88179-004-7, ISBN 3-928427-03-2, ISBN 3-88179-009-8, ISBN 3-928427-05-9)