＞４０１
>Surprisingly, many classical recordings issued before 1972 are not protected
>by copyright. Law in this area is extremely convoluted, because before 1972,
>the first "fixation" of sound (the original master tapes) was eligible for
>protection, but the records and tapes made from them were not. Thus, an LP
>or tape issued for public sale before 1972 is public domain and can be freely
>used for any purpose--as long as the music contained therein is also public
>domain.

この記述が正しいのなら、今後まだまだ廉価再発盤のリリースを期待できそう。
米国の復刻再発レーベルに頑張って欲しいもの。スレ違いだったらスマソ。。。