Sound recordings have proven to be irreplaceable primary sources for disciplines like linguistics, musicology, ethnomusicology and sociology. Their fragile physical nature has activated a number of counter-actions aimed at prolonging the life expectancy of their content. Methodological issues have been raised in the past three decades, considering the relationship between the physical object and its (digitized) intangible content, which is not only complex but develops over time. This article re ects on the role of the emerging discipline known as ‘digital philology’ in the long- term preservation of audio documents, pointing out how some concepts (such as authenticity, reliability and accuracy) may require a ‘customized’ (as opposed to a ‘ready-made’) approach in the preservation work ow – mainly depending on the type of the archive: unique copies, eld recordings, electronic music, oral history, to name some representative cases. The set-up of the laboratory for sound preservation at the Centro di Sonologia Computazionale (CSC) of the University of Padova, Italy, represents one customized approach in which conscious methodological decisions support philologically informed digitization e orts. The methods affect the results, and ultimately the consequences are not merely technological but cultural.