File extension mpga is used by following file type(s):

File extension mpga file type description:
Mpeg-1 Layer3 audio stream

The same as mp3 audio format.

MPEG-1 Layer III Audio Stream. This standard has evolved from early MPEG (The Moving Picture Experts Group) work. It is an audio compression technology that is part of the MPEG-1 and MPEG-2 specifications. The Fraunhofer Institute developed MP3 in Germany in 1991. MP3 uses perceptual audio coding to compress CD-quality sound with almost the same fidelity. Mime: audio/mpeg

that open mpga files:
Apple iTunes for Mac (Apple OS X)
Apple iTunes for Windows (Microsoft Windows)
Microsoft Windows Media Player (Microsoft Windows)
Winamp (Microsoft Windows)