Yes, Mp3tag can in fact be used to find duplicates in different sub-directories. ohrenkino gave wrong advice. To accomplish the task, simply click on "Change directory" icon and select the initial directory you wish to compare against. Next, click on the "Add directory" icon to add the second directory you wish to compare with. Now you will have two directories in Mp3tag. Then just click on the "Filename" column heading to sort the column. Now you can see all the duplicates and delete them as you like or manipulate them any other way your like. There are several ways to solve problems. If ohrenkino is reading this thread, please retract your advice.