I have over 100gb of music organised in folders, that I started building up well over a decade ago. Sadly much of it was ripped to WMA, so will not play on my iPad or many CD players. Is there a routine, Windows or Mac, free or pay, that will convert all WMA files in the file structure and put the MP3 conversions into the same place? With guaranteed MP3 files of at least the same quality as the original WMA? If there isn't, what is the converter that gives the best results and is easy to use with bulk WMA files?