From <a "href="http://188.8.131.52/~mark/lilypond/menuet.ly">this .ly file</a> I generated this <a href="http://184.108.40.206/~mark/lilypond/melody-page1.png">image</a> and <a href="http://220.127.116.11/~mark/lilypond/melody.mp3">MP3</a>.
The score to midi to audio pipeline is not exactly performance quality. For example, the lower clef is overwhelming the upper clef. That's one of the many things that a human player is supposed to notice and automatically change, mainly by making the repeating G much much lighter. I've also just got the standard junk voices in my <a href="http://timidity.sourceforge.net/">Timidity</a> install.
Going from scores to a performance grade MIDI is, as we say in the field of computer science, <a href="http://www.catb.org/~esr/jargon/html/N/nontrivial.html">"nontrivial"</a>. Apparently, <a href="http://www.sibelius.com/">Sibelius 3</a> is getting good enough that it's starting to replace performers at some musical theaters (much to the union's distress).
I suspect that eventually commercially performed it will be like compilers and typesetters. A well trained human, at full focus and at the top of his form, can usually write ASM or typeset text better than a computer. But not as many people are as good as they think they are, nobody is their very best all the time, and besides, people are expensive.
It's really too bad, already trying to be a paid classical or orchestral performer is, at best, usually a ticket to frustrating poverty, completely unfair for such a demanding and beautiful skill.
Now, back to bed for another 3 hours (two cycles), before going off to work.