The chamber choir CONSONO, Cologne, was founded by Harald Jers in 2001. In relatively short time, it has achieved an outstanding reputation by winning numerous national and international choral competitions, such as the Deutscher Chorwettbewerb (German Choir Competition), the International Chamber Choir Competition of Marktoberdorf, as well as competitions in Maasmechelen (Belgium), Cork (IRL), Gorizia (I), and Debrecen (HU). Hence, CONSONO is among the most successful chamber choirs in Europe. Since founding, CONSONO has been known for its radio and TV broadcasts, CD productions, and most notably for its participation at international choral competitions and at renowned concert series. The repertoire of the choir is widely varied, ranging from Baroque oratorios and 19th century Romantic choral music to recent choral works and premières of 21st century music specifically composed for the ensemble. Of particular interest is the mastering of interesting and mostly unknown a-cappella works by contemporary and Romantic composers from different countries and their stylistically authentic performance on the highest level of art possible. The choral and practice activities centre on the wide ranging possibilities of vocal expression including special knowledge of vocal acoustics. These are the prerequisites for a stylistically adequate work with the choir. Combined with an effective conducting style, a particularly time efficient mode of work on the music is achieved. In doing so, Harald Jers combines his knowledge of the historically informed performance with his own research on choral and room acoustics, shaping the intensive and expressive sound of the ensemble.