Format Factory: The ultimate conversion software for PC
Format Factory is a multifunctional converter software that’s able to convert all types of video, audio and image files. Complete, powerful and free, it’s a must-have conversion tool.
Audacity: Digital audio editor
Audacity is a free open source digital audio editor and recording computer software application, available for Windows, macOS/OS X, Linux and other operating systems.
Lame: High quality MPEG Audio Layer III (MP3)
LAME is considered the best MP3 encoder at mid-high bitrates and at VBR