M4A

Files with a .m4a extension are container files that store audio data. The audio data that is contained in the .m4a files is encoded using the MPEG4 Part 14 format. Like MP3 files, files with the .m4a extension are compressed, but the compression technology used to create .m4a files results in a higher quality of sound. File compression makes the files more manageable, decreasing the file size. This allows them to be downloaded from the Internet more quickly and allows the M4A file to take up less storage space.

- - Wikimedia

MP3

MP3 is an audio coding format for digital audio. Originally defined as the third audio format of the MPEG-1 standard, it was retained and further extended—defining additional bit rates and support for more audio channels—as the third audio format of the subsequent MPEG-2 standard. A third version, known as MPEG 2.5—extended to better support lower bit rates—is commonly implemented, but is not a recognized standard.

- - Wikimedia

Step-By-Step to Convert M4A to MP3

Interface

Step 1. Download and install the program, then double click it to run it, and then you'll see the main interface of the program.

Load Files

Step 2. Click "Add File(s)" button. Here you can select "Add Video" or "Add Folder" button to add files as you like.

Profile

Step 3. Click the drop-down arrow right beside the "Profile" column and select your desired video format from the drop-down list.

Edit

Step 4. Click "Edit" button to customize the output video like Effect, Trim, Crop, 3D Settings and Watermark.

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