The “Scrapbook Series” was a popular, long-running BBC broadcast launched in the late 1920s; conceived as a ‘microphone medley’ or ‘sonic pageant’, it revisited the acoustic highlights since the advent of recording technology. This remarkable audio documentary provides the starting-point for this Chapter, which explores essential links between cooperative broadcasting policies, Woolf’s heightened acoustic sensibility in the 1930s, and the era’s awareness of itself as being, for the first time in history, dimensioned by reiterable sound. Retracing the evolution of the European Broadcasting Union via sound archives, wave-length legislation, and primetime BBC programmes, the chapter charts the richest, most overlooked experiments in cultural diplomacy on air, designing a safer, more harmonious Europe which linked common listeners at home via the boldly trans-European resonance of music.