There's no doubt that MP3 is king when it comes to all things audio on PC or Mac. If your music or audio isn't in MP3 format then you need a simple way to convert it which is what All2MP3 does.
All2MP3 converts music files directly into MP3 audio format using AppleScript. After starting the program, you simply drag and drop files onto the program window and select the quality of target files. All you have to do is click on the All2MP3 button and the conversion process starts. The program converts MPC, APE, WV, FLAC, OGG, WMA, AIFF and WAV.
There are very few options beyond that other than you can choose whether you want the application to delete the original files automatically or keep them. It does not recognize all formats although it does support the major ones listed above. Audio quality is excellent and the conversion process is fast but it would have been nice if you could select exactly what bitrate you want to convert to. As it is, the default is 128Kbs although Super apparently refers to 320kbps.
All2MP3 is the simplest MP3 converters for Mac that you'll ever find without plugins - don't look any further for one-off conversions.
