Harald Jers is founder and conductor of CONSONO chamber choir. The choir consists of about 35 singers from all over Germany and reheases regularly at 7 to 9 weekends during the year in Cologne. A special trademark of this chior is to work out interesting unknown a-cappella-repertoire by romantic and contemporary composers from all over the world. CONSONO received several national and international first prizes at highly respectible choir competitions.

Chamber choir CONSTANT at Antoniterkirche was founded in 2006 from its conductor Harald Jers and counts about 28 singers. Rehearsals are on Thursdays from 8pm to 10pm in the hall of the parish of "Antoniterkirche" in the city centre. The repertoire is stylistically spread from Renaissance to modern choral music with mainly sacred texts.

Harald Jers researches in in the field of musical acoustics and room acoustics, which lead to important scientific basics of the analysis of the human voice in choirs. This acoustic knowledge is combined with his professional skills as conductor and singer during his rehearsals with amateur and professional choirs.