Theodor Hassek derived from a musical family and was born on April 11th 1929 in Linz. Already at the age of 12 he played piano, began creating compositions and took lessons at the private music school Potansky.
From 1946 Hassek studied composition at the Vienna academy for music and performing arts with Joseph Marx, Otto Siegl and Rudolf Kattnigg as well as piano with Eugenie Wild-Volek and Ludwig Czaczkes. He performed repeatedly on the piano interpreting his own works. His pianistic repertoire ranged from easy entertainment music to highly demanding classic piano works.
He completed the state exam for piano in 1950 and graduated in composition (theory) 1952. In this period he composed most of the romantic piano works and also some for chamber music. Apart from this Hassek had a try in chansons. After a while in bread-and-butter jobs he began 1962 performing schlager and dance music in the 3 person band “The Gamblers”. Together with his cousin Erhard Hassek he performed in bars and nightclubs in Germany. Later they were engaged on a regular basis at Intercont Hotels in Geneva, Frankfurt, Hannover, Düsseldorf and Vienna.
The composition of neoclassical piano works started in 1968 followed by a time of active musician at various Vienna “Heurigen”-Restaurants.
He discontinued his career as an active musician end of 1982 and began to work as a reader and arranger for renowned Vienna music publishing companies in July 1983. He composed a number of melodies dedicated to entertainment music - some of them were recorded by popular big bands also made a few jaunts into folk music.
Although he retired officially end of 1988. Inspired by the common piano playing with Helmut Hofmann he further composed piano and chamber music.
In his last years of life he became interested in spiritual music (2004). Hassek meticulously became acquainted with this matter and composed two mass for mixed choir and organ. The completion of the Missa Brevis in F major was already affected by health problems. Theodor Hassek passed away on October 28th 2009 in Vienna due to a heart disease. His final resting place is at the cemetery of Aspern in Vienna’s 22nd district.