When recording in 320kpbs or 192kbps AAC, it produces M4a on iTunes.
To convert these files to be either MP3 or WAV you can simply do this via iTunes following these steps:
Step 1: Select and highlight the desired audio track on iTunes.
Step 2: Select File along the top bar.
Step 3: Click Convert, this will bring a selection of options.
Step 4: Finally, click 'Create MP3 Version'
This will then generate an MP3 version in the same album/location on iTunes.
In some cases, it may say 'Create AAC Version', If this is the case, you can follow the steps below before following the steps above:
Step 1: Click on Preferences and find General.
Step 2: Select and click the 'Import Settings' button.
Step 3: Find 'Import Using' and you can select the desired import encoder.
Then you are good to go with converting your audio file.