Jamie,
First, Mozart wasn't Italian. Second, Mozart was Classical. Wagner was Romantic. The biggest difference between the two is the two different periods. Perhaps you simply prefer Classical to Romantic?
Walter, I know Mozart wasn't Italian, that's why I said in my post "(even though...). His operas, though, were in the language and style of other Italian composers. It has more to do with style. I find Wagner's style very abrupt and lacking in subtlety and emotion. I think it is more of a German issue, because I also see it in Strauss and Brahms as well. Even though my favorite composer is Gustav Mahler (a Romantic period composer and yes, I know he's Austrian but he did much of his composition in Germany) I see some of that abruptness in his works, particularly in his purely vocal pieces (e.g. Das Lied von der Erde). Mahler, on the other hand, is capable of a wide range of emotion, even in one piece as his Second Symphony readily demonstrates - if you haven't heard that live it is the most thrilling, emotional piece you ever will. The only one for me that comes close is contemporary composer Morten Lauridsen's "Lux Aeterna". I don't think that the style is the issue at all. Tchaikovsky was another Romantic period composer and his music is amazingly expressive - has any composer captured pure sadness the way that he did in his Sixth Symphony? Verdi is another wonderful, expressive Romantic period composer, as is Debussy.
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