It is interesting to observe how the soundtrack releases accompanying the Matrix trilogy have evolved through the series. Whereas the Don Davis music for the original film The Matrix seemed to be released as an afterthought to the "from and inspired by" CD, the equivalent CDs were equal partners on the double-CD release for The Matrix Reloaded. On with the conclusion to the trilogy there is no "from and inspired by" CD at all, and it falls largely to Don Davis to provide the matrix sound on this release. We say "largely" because Juno Reactor provide rhythmic support on three tracks (with Ben Watkins composing their material), and "In My Head" by Pale 3 is the single token artist track. Although Davis has provided a consistent and unique soundscape to the worlds of the Matrix, it too has evolved over the course of the three soundtracks. Although the third movie provides swarms of the emotionless machines as the main foe, the music emphasises the human emotional aspects as it focusses on the shared plight of the inhabitants of Zion and the personal journeys of Trinity and Neo.
If you are familiar with the music from the other films you will know what to expect, but the music is still evolving into this final installment. It provides resolution to the previous development, both on the grand scale and at the personal level. People have called Davis' music for the Matrix films Wagnerian because of its grand concept and scale spanning three films, with huge orchestral and operatic sounds. Davis himself clearly describes the story in these terms with its mythological and religious resonances. Two tracks directly reference works by Richard Wagner - "Kidfried" is "Siegfried" and "Neodammerung" is "Gotterdammerung", two operas from Wager's Ring Cycle. It is possible to take analogies too far, but worth noting that Wager liked brass instruments, inventing the "Wagner Tuba". He also made extensive use of leitmotifs, themes to represent people. Davis doesn't do this to the same extent but does employ thematic ideas, notably for Trinity and the Matrix motif itself.