MPA is an audio file that closely resembles thte audio-only formats like MP2. This audio format is small in size but with minimal quality loss. Technically, MPA files use MPEG-2 compression, which is known to offer small file size with original sound quality. MPA can be opened on most OS platforms and come with a .mpa filename extension.
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M4A is a filename extension for AAC container format and is developed by Apple Inc. M4A music is bought on the iTunes Store and does not come with DRM protection. In terms of quality, M4A is better than MP3 because it is lossless but still compressed. This means that it occupies less storage space and doesn’t lose quality over time.
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