It's impossible to convert them directly. The only real way to do it is by ear - construct a MIDI by listening to the different parts of the MP3 and tracking those yourself.
actually, I found a couple of programs that will do it, but they all are shareware with crappy quality and I wouldn't even want to think about reconstructing this piece. It's the Noir opening, and theres no way in hell I could do it by ear.
I think the problem is that the song is about on par with the technicality of Bebop's Tank!. And the program is trying to render it with just one instrument. If anyone find the Noir opening song as a mid, let me know. The name of the song is
Copperia no Hitsugi.
I did have a program a while ago that tried to do it. It was all right for single instruments, but it couldn't just take an MP3 and convert the whole thing.
It IS possible with music which only has 1 instrument playing at once. A really good converter can handle 2 instruments at once but anymore than that and it won't work very well.
99 percent chance that the above post is 100 percent correct.
You can always download All Converter (sorry, no link, but serch under google for that and wavs and mp3 and you'll find it) and turn it into wav sounding pretty much exactly the same, and then if you use multi samples and play it as an uninterruptable sample it'll work as backgroud music, no problems.
Why the hell am I on the computer at 1 in the morning? No, don't answer.