Prior to the project, tons of thousands of audio items dating back to the invention of the first sound recorders were waiting to be discovered in museums, archives and libraries throughout Europe. 24 partners decided to take up the challenge to gather those sound collections, to enrich and aggregate metadata for them in order to fit on an online platform, Europeana.eu, to improve the domain constraints caused by copyright, to innovate with user-friendly tools, and last but not least, to communicate about the project and its outcomes.