The Paris-based Museum of Music keeps archives from luthiers, instrument makers and musicians. Several hundreds of these documents are now accessible online. These archives testify to evolutions both in instrument-making and in the musical scene during the 19th and 20th centuries. In particular, they comprise registers from Érard, Pleyel and Gaveau, from Nicolas Lupot, Gand and Bernardel’s instrument-making workshops, and they also include substantial correspondence between luthiers Chanot and Chardon. The main part of these archive collections - comprising extremely fragile documents, sometimes in poor condition - was digitized and uploaded for safe-keeping and accessibility purposes, as testimony.