This album is the sequel to Martin O'Donnell's and Michael Salvatori's Halo 2 Original Soundtrack Volume One. Due to the time when the first was released, they were unable to use all the in-game music in that album. This release contains 12 tracks, each one being a multi-part movement from various levels and areas in Halo 2.
Audio is ripped using cdparanoia (non-Windows equivalent of EAC) and encoded using aoTuV Ogg Vorbis at q3. If you want high fidelity, I'd recommend you buy the album or something (it's worth it if you like classical music or enjoy the music from Halo 2).