Finding duplicate files by listening to your entiremusic libraryis impractical.
AllDup
Scan multiple folders at once.
Compare using multiple factors.

Scan inside ZIP and RAR files.
Can be hard getting started.
AllDup includes an impressive set of features for a free duplicate file finder.

It seems to have options only seen in the premium versions of similar tools.
This level of precision sets this one apart from other duplicate file finders.
There’s both a normal and portable version of this duplicate file finder.

Duplicate Cleaner Free
Scan multiple file times.
Tune your file search.
Control what you want to remove.

A trial of a paid edition.
Its interface is easy to use and has an impressive range of options to fine-tune your search.
The selection assistant is particularly useful for quickly marking files for deletion based on your criteria.

This program is only a trial of the professional edition.
Similarity
Well-organized interface.
Compares based on the file content.
Interface is pretty ugly.
Similarity is a stellar freeware program that searches for duplicate music files.
It uses advanced algorithms that compare audio files based on sound content rather than binary patterns.
Similarity also looks at MP3 tags and has an experimental mode for deep scanning.
Results are shown in the Results tab.
Duplicate Music Files Finder
Simple to use.
Scan folders and subfolders.
Duplicate Music Files Finder also comes with a built-in set of tools for managing your files.
There’s also a quick tag editor and you could play duplicate files to check them before deletion.
Easy Duplicate Finder
Scan multiple drives and folders.
Might be too simple for some.
This duplicate file finder holds true to its name.
It’s very easy to use.
Click through the wizard to see the results and find the options for deleting the duplicate music.