During a journey Mozart made from Vienna to Berlin in 1789, he visited Leipzig and attended a rehearsal of Bach's motet Singet dem Herrn ein neues Lied (BWV 225), sung by the Thomanenchor under the direction of Cantor Johann Friedrich Doles. One of the boys in the choir at the time, Friedrich Rochlitz, would some years later become a musicologist, and he bears witness, in the Allgemein Musikalischen Zeitung in 1798, to the artistic revelation that struck Mozart: "The choir had sung but a few bars, when Mozart interrupted us, crying `What is this piece?', and it seemed that his entire soul was then to be found in his ears. When we had completed the motet, he called out, filled with joy, `Now that is indeed quite something! There is much to be learned here ... bring it to me!' But we had no score, so we gave him the part-copies, and then it was for us a great joy to see with what enthusiasm Mozart arranged the parts--his hands full, paper spread on his knees, and on the surrounding chairs--and forgot all else until he had absorbed all that Bach had set down."