ABSTRACTThe Enlightenment is flanked by an ‘acoustic turn’ which begins with the highly relativised ‘tempered attunement’ in the latter part of the seventeenth century. This new temperament permits a musical modularity that departs from the existing mean‐tone temperament. At the same time, it organises the subtle interplay of harmonic and melodic structure through physiological references. As will be shown here by the examples taken from Jean‐Philippe Rameau (1722), Johann Mattheson (1725), and Denis Diderot (1751), the aesthetic reception and production of man as a stringed instrument was conceptualised, in new and acoustically precise fashion, within this area of tension. Johann Gottfried Herder also inscribes himself within this transference from musical theory to physiology. At the same time, in the Viertes Kritisches Wäldchen (1769), he reduces the interleaving of melody and harmony to the single tone, which produces a direct, sympathetic relationship between a specific acoustic vibrancy and emotional stirring. In so doing, he abandons the harmonic relations and the broad variance of tempered scales of the eighteenth century. Insofar as Herder ultimately, in Calligone (1800), exhibits interest only in the succession of individual tones, he propounds a new genealogical order of knowledge. Parallel to this, the music of the early nineteenth century undergoes a standardisation of semitone steps which permanently abandons the subtle relationship between the harmonic and melodic structure favoured in the Enlightenment.