To the People
In japan, All files open to the public on this site are certainly lawful.
But, if you do not live in Japan, You might do not have to use files.
You should check the law of your country.
As proves too often true for works, like this 1942 recording, that fall under the aegis of the 1909 Copyright Act, it is not easy to figure out if the underylying work enjoys any claim to protection under U.S. law. Perhaps, after all, it was not published with the proper formalities, here, and thus fell into the public domain.
In this case, though, it looks like we can dodge those complications. U.S. copyright law affords exclusive rights only to copying, creation of derivative works, public distribution, public performance, and public display. See 17 USC § 106. So long as I listen to a MP3 solely via streaming, without saving a copy, it is hard to see how I've violated any of those rights. Perhaps Digirock, Inc. has violated U.S. law by offering me the MP3, but that is no concern of mine (and probably not much of a concern to Digirock, Inc.).
That legal scenario suggests an interesting conclusion: an offshore copyright-free zone—one set up by intellectual pirates or in a stubbornly independent country—might give U.S. residents ample, free, and legal access to all sorts of copyrighted works—even ones protected under U.S. law.
[Crossposted at Agoraphilia and The Technology Liberation Front.]