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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MKV is a container format for holding multiple audio, video, picture, and text data such as subtitle tracks. It is similar to other common containers like MP4 and AVI, although MKV is open in the specification. For video contents, MKV uses a .mkv filename extension, .mka for audios, and .mks for subtitles.
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