The acclaimed series of complete Bach cantatas with the Amsterdam Baroque conducted by Ton Koopman, originally begun on the now-defunct Erato label, has been revived by Challenge Classics. Ton Koopman and his choir and orchestra continue to uphold a standard of tremendous vividness and joy in their immaculate performances of Bach's most impressive opus. The Amsterdam Baroque Orchestra, founded in 1979 by Ton Koopman, are a group of musicians from all over the world, with a particular passion for the Baroque. Their recordings have won numerous awards. The Amsterdam Baroque Choir, founded in 1992, consists mainly of young Dutch professional singers. Born in Zwolle, Holland, in 1944, Ton Koopman decided very early in his musical studies to specialize in the 17th and 18th centuries, using authentic instruments combined with a performing style based on sound scholarship. Begun in 1994, this series was awarded the 1997 Deutsche Schallplattenpreis "Echo Klassik" in Germany. The series will continue to feature the scholarly contributions of Professor Christoph Wolff, one of the world's leading experts on the music of Bach. Each set includes a thick, informative booklet. The cantatas of volume 19 can be divided into three groups. Four works (BWV 72, 88, 129 and 193) belong to the third Leipzig series, lasting from 1725 to 1727; five (BWV 145, 159, 171, 174 and 188) belong to the group known as the Picander cycle of 1728-29, which was not completed or has not survived complete; two works (BWV 51 and 117) belong to the period after 1730, in which Bach composed new church cantatas only sporadically. His first five years as Thomaskantor cost Johann Sebastian Bach unusual effort, as he had undertaken composing church cantatas appointed for each Sunday more or less by himself. He was not contractually obliged to do so, but he adhered quite strictly to this plan at least for two years and loosened it a little for the thrid yearly cycle! , which was spread over two or three years. Even so, Bach never got stuck in a routine, as he was constantly discovering new facets of the canata genre.