Anybody that knows me can tell you that I've been a long time admirer of the folks who do audio preservation and restoration. Here in the the US of A, the center for that kind of activity is housed in the Library of Congress (LOC). Their new state of the art facility in Culpepper Va (The Packard Ctr) which was opened a few years ago, has begun to make digital transfers of some of their holdings available through the "National Jukebox".
Check it out,.. and while you're there, even if you have no interest in Opera, you should take a look at the Victrola Book of the Opera to see how elegantly something like this can be done online. (warning, big ass stream)
http://www.loc.gov/jukebox/?loclr=jb_004
