There's not even a need to extend existing formats. Both AIFF and WAV support metadata chunks. But BWF (Broadcast WAV) is a widely used standard that has well defined chunks for XMP and if you need files larger than 4GB, the RF64 spec extends the format to ~16EB.
The company I worked for a few years ago had a huge replacement cycle and wanted me to "make sure there aint no data left no how". So, being in Nashville, I picked up an old 3M tape degausser from a recording studio that was ditching its analog gear. Many-a-disk have been wiped with that thing. Even better is that it's strong enough that it can take out some chips as well.
Probably not the first to point this out but I got tire of scrolling so...
This was first discussed right here on
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