Audacity is a software that helps you merge you MP3 and Wav files. Audacity is software developed by a group of volunteers. It is a free software and is distributed by the GNU General Public License (GPL). It is a audio editor that supports an array of operating systems like Windows, Mac OS X, GNU/Linux and so on.
You can use this application to mix sounds and edit different kinds of sound files like MP3, WAV, AIFF and so on. It can also be used to change the speed of the recording. After installing Audacity, to merge files, complete the following:
1. Drag and drop audio files.
Note: Alternately, click File and then select Open dialog.
This displays the audio file in a separate window.
2. Select one of the tracks with a left-click.
3. Press Ctrl+A to select the song.
Note: Alternatively, select only part of the track that you want to use.
4. Left-click on the location of the other track where you want to paste the selected track.
5. To merge, click the position at the very end of the track and press Ctrl+V.
This merges the tracks. Repeat this process till you have merged the audio files that you need.
6. Click File and select Export to save the file as a new merged audio file.
You can choose to save these files in different formats, including MP3, Wav, flac, ac3, and so on.