Download the Audible Manager and choose the "Listen on My Computer" option. This will make Audible work with the media player on your PC and install the ".aa" codecs that is necessary for the conversion.
Double-click the .exe file to open the manager. Log in with your Audible user name and password.
Click "Edit," then "Options." Write down or remember the folder shown under "Location of Audio Files." Click the "X" to exit the program.
Download the Audible filter. Double-click the .exe file to install. This filter is necessary to use the newest version of the Audible Manager.
Download Goldwave from the Resources section. Double-click the file and click "Unzip." Alternatively, if you have an extraction program like WinRAR, right-click and select "Extract here."
Go inside the extracted folder and click "Goldwave 5.06.exe." Go to "File" then "Open" and browse to the folder location you wrote down earlier. The default location is: "C:\Program Files\Audible\Programs\Downloads."
Double-click the audio book you wish to convert. If you receive a pop-up requesting activation, type in your Audible password and username and click "OK." The audio book will load into Goldwave for editing.
Select "File," "Save As" and then scroll to "Save as type" to choose "MPEG Audio." Also change "Attributes" to "Layer-3 ACM 44100Hz, 128 kbps."
Click "Save" and wait for the conversion to complete. If your PC is missing the "Lame MP3" encoder, you'll receive an error message from Goldwave with a "Download" button. Click it and the codec will automatically download and install.
Continue the process for each audio book. Open the default folder to find the converted MP3s.