>...Sony Classical or whoever will 'protect' the particular performance of a LvB's symphony, when the work itself is in public domain.

Yeah, the performance of that artistic production is itself an artistic production subject to those same copyright laws. Similiar to your example, one of the things that really irks me about copyright law, being a big fan of paintings, is that a picture of a painting is itself copyrighted. I think that is going a little too far, it is hardly like a picture of a painting is an "artistic production".

Your example of "try before you buy" may (MAY) be legal under the fair use exceptions of the U.S. (just for general info, not that it matters much to you in Croatia). If it is non-commercial, is not a substantial portion of the work in question, and, most importantly, will not effect the potential market or value of the work, it just might fall under fair use.

I'm not a lawyer (though I play one on TV). If you get arrested, don't say, "well, Ninti said I could".