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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MP4 (MPEG-4 Part 14) is a video container format based on QuickTime MOV. But unlike MOV, it adds support for other MPEG features. MP4 supports video (MPEG-4 Part 2 and MPEG-4 Part 10/H.264), audio (MP3, AAC, SLS, TTSI, and ALAC), and subtitles (MPEG-4 timed text). It’s this codec combination that gives MP4 its flexibility.
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