"I have recorded several lectures on my iPhone using iDicto and the format is .aiff. I would really like to convert them to .mp3 so that I can put them on a CD and use them in my car and whatnot. Is there a way/tool to convert .aiff to .mp3? Thanks in advance!"
--- from forums.macrumors.com
How to convert a song from .aiff format (more commonly seen as .aif on Windows systems) to other audio formats like MP3 and AAC? Generally speaking, there are two ways to get it done:
For Mac users (and some Windows users), iTunes (including iTunes 11) will enables them to convert songs in the iTunes library to another format. The converting will generate a copy of the audio in the format you’ve chosen, which gives you the alternative to either keep or delete the original file. When you convert an audio from a compressed to uncompressed one (for example, from MP3 to AIFF) you wouldn't notice any reduction in sound quality. However, while converting from an uncompressed to compressed format (eg. from AIFF to MP3, AIff to AAC), you should note that it will inevitably lose the sound quality.
1. Choose iTunes > Preferences > General > Import Settings.
2. From the Import Using pop-up menu, choose the encoding format that you want to convert the song to, and click OK to save the settings.
3. Select one or more songs in your library and choose File > Create New Version > Create Format Version.
The song in its original format and the newly converted song appear in your library.
Important: You can convert iTunes Store purchases only if they’re iTunes Plus songs.
For most Windows users who do not have the iTunes, or for those who have iTunes but don’t want to use it to do the conversion since the quality loss problem, a third-party AIFF Audio Converter is needed. Doremisoft Video Converter (Video Converter for Mac) is the exact converter that can help users conduct the conversion from AIF to MP3, AIF to AAC and more with ultrafast conversion speed and would not lose any sound quality.
Download and start up the converter, and then import the source AIFF/AIF audios to the converter by clicking "Add Files". You can add several files to it at one time thanks to the batch conversion function.
Open the format box of "Convert to", and then choose a proper output format from the "Common Audio" tab in the drop-up list. If you want to convert AIF/AIFF to MP3 or AIF/AIFF to AAC, please choose the MP3 (*.mp3)/AAC (*.aac) preset.
After the settings, simply press the big blue "START" button on the bottom right to start converting AIFF/AIF to MP3, AAC, etc. The conversion will only take you a little while before it is perfectly done.