The French research infrastructure for written heritage Biblissima started in 2012. It included in its second phase, from 2021 onwards, a subgroup focused on musical written heritage, which aims at enhancing the use and accessibility of music data in Biblissima's ecosystem and, more specifically, in its updated central web portal. This paper presents first results of this research group. It offers an overview of available online complementary resources pertaining to pre-1600 music and music books, an assessment of their technological and scientific possible interactions, and first experiments on ways of merging them into interconnected user interfaces based on the IIIF standards. An alignment algorithm has been developed for combining data on musical works and manuscripts available in DIAMM and online digitizations of the BnF. Methods for collecting more metadata on music manuscripts’ contents through the use of an AI classifier are then discussed.