With 750 printed reviews of matters related to music, the Allgemeine deutsche Bibliothek is a major source for the study of musical discourse in the Enlightenment. The central topic of the book is music criticism in relation to its claims and its implementation. The investigations in it are devoted to the locus of music criticism in the intellectual landscape of the Enlightenment, the place of the »Allgemeine deutsche Bibliothek« in musical life at the time, and its mutual connections with the contemporary book and music market. Numerous sources, including hitherto unknown passages from posthumously discovered letters by Friedrich Nicolai, help to illustrate the interplay of operative contemporary factors.