During his studies he was a member of the Akademie-Kammerchor, played organ concerts and appeared as a percussion substitute with the Wiener Symphoniker.
In 1961, while working as a scientific advisor at the Anton Bruckner Private University, he conducted the first Brucknerfest in Linz and in nearby Sankt Florian, He worked as a freelance musician from 1962, was in contact with international avant-garde artists such as Bruno Maderna, Günter Kahowez and Francesco Valdambrini and finally founded the Neue Ensemble in 1968, a very important orchestra for new music in Upper Austria (collaboration with Eela Craig), as well as his own music publishing house, where, in addition to his own works, those of Walter Pach, Richard Kittler, Erich Urbanner and Augustinus Franz Kropfreiter appeared in the Edition Neue Reihe.
On the one hand, the publishing house sees itself as a promoter of the work of Alfred Peschek, but it also strives to attract new composers.
[3] Die Werke des Linzer Avantgarde-Komponisten wurden weltweit aufgeführt und mehrfach mit Preisen ausgezeichnet.
[5] In 1988, Peschek was the founding chairman of the International Society for Contemporary Music Upper Austria branch and vice-president of the artists' association MAERZ.