In Adorno's very early writings the idea of ‘musical material’ itself remains as yet rather unfocused. It is only later that the concept receives its most comprehensive formulation - that is, in Philosophie der neuen Musik. Indeed, the whole argument of that book is predicated on the idea that it is not what ‘musical sounds’ are in themselves – their natural, physical qualities – that is significant, but rather what they have become in any particular instance. Adorno maintains that it is in the relationships of sounds one to another, which are historical in character, that social relations are sedimented, albeit in purely musical terms. Nevertheless, although Philosophie der neuen Musik offers a version of the concept in its apparently most complete form, it is argued here that a clearer understanding of what is meant by ‘musical material’ is to be gained from a careful examination of how the idea of the mediation of music and society unfolds in Adorno's work from the late 1920s up to the period of his exile from Germany in the mid-1930s.