AC3, short for Dolby Digital AC-3, is a new generation of multi-channel digital system for home theater. It contains five channels for normal-range speakers and one channel for the subwoofer driven low-frequency effects, and so it is also known as 5.1-channel. Audio files could be compressed to as small as 1/12 by AC3 with some loss on sound quality correspondingly. 

Zune is the name of both services that obtain and share the media content and a brand of Portable Media Player developed by Microsoft like iPod of Apple Inc.

Xbox is a video game console competing intensely with the Nintendo GameCube/Wii or Sony's PlayStation/(PS2/PS3).Microsoft has published versions Xenon, Xbox 2, Xbox FS, Xbox Next, or NextBox, XBOX 360.

You can convert ac3 to wma first, then play them on Zune / Xbox. Please install DVD players such as WinDVD player or PowerDVD player on your Windows, which include the AC3 decoder. Because wma format only supports stereo or mono channel, please configure output audio channel as stereo in properties of AC3 decoder.  Or install the ac3 decoder. In VISTA the codec is bundled as default.

Download Zune Xbox Converter to convert AC3 to Zune/Xbox. Then use USB or networks to transfer the wma file. Or burn the files to CD/DVD, play disks on Xbox easily.

MPC means MusePaCk (.mpc), which is a completely free and high-quality audio format developed by Andree Buschmann in 1997. With better sound quality and faster encoding speed than MP3, it is now believed to be the best lossy codec suitable for listening music. But ItÃÔ said that only OEM Cor. develops Walkmans that support MPC format at present and which is only used by few people who persue higher-quality sound. And as MPC lacks of support from both hardware and software, and itÃÔ less well known, itÃÔ mostly impossible to replace MP3.

To play mpc on Zune / Xbox, please install the appropriate mpc Directshow filter/decoder/codecs (RadLight) for the mpc file to wma.