not completely sure if either of these will help with what you want
i know that with both of them, you can use them to convert music to other formats.
see, i had a lot of music saved as wma. and i used these programs to convert them to mp3. at first, most of them were at like 96 kbps. but when i converted them into mp3's i changed them to be 192kbps.
it did make them sound a lil bit better, so that may help with what you're looking for
audio conversion studio
or
nero 6
nero is awesome in every way. you can do pretty much anything you want to with music in there. and a lot of files and movies and such as well
but the audio conversion studio lets you have a 30 day free trial. and there are no limitations either
another good one is virtuosa
don't know if it converts or anything though
but it's still a nice program with a 30 day free trial(no limitations)