Converting audio files from the MP3 format to Atrac3 (Adaptive Transform Acoustic Coding) is a simple step-by-step process once your computer has the right software and drivers. Atrac3, developed by Sony, compresses audio files while maintaining the quality of those files, allowing for greater storage capacity and portability.
Download the Atrac conversion software if your computer didn't come with it. A number of programs will do the job; search online to find one. Some programs must be purchased to download, others may be free.
Open the program once it downloads. Different programs may have slightly different settings and steps to converting; all should be pretty basic.
Locate the folder where the MP3 files you wish to convert are stored, and bring them into the main window of the conversion program. Do this either by clicking "Select Files" and following the cues or by dragging them from another window.
Select the Atrac format (.aa3, .oma, .omg and .atp are all similar Atrac file abbreviations; .aa3 is Atrac3) to convert the files to. Do this either by going through the Settings menu or clicking the Atrac icon, depending on the program you're using.
Select the name and location for the folder the converted files will end up in---My Music or My Documents, for example.
Click "OK" or "Convert," depending on your particular software, and the files will convert and transfer to the output file you selected.
Use the "Help" or "About" feature of the software you're using for exact settings, terms and more details on using it.
Be careful when downloading that the program doesn't come with any harmful viruses or spyware--only download from sites you trust and/or make sure your antivirus program is running before proceeding.