Ace Combat 04 Shattered Skies boasts a serious narrative where the relationship between events and characters comes to the front intricately. Every scene is supported by the game's realistic setting, and certainly the music contributes with its dense soundscape.

The soundtrack leads with a fierce yet cool harmony that Tetsukazu Nakanishi, the AC04 sound director, establishes. It consists of determined brass and tense strings supplemented by various distorted beats with a steady tempo. (It conjures almost no image of the futuristic techno in the previous game, Ace Combat 3 Electrosphere, even though the same man was behind it.) "Tango Line" begins with an uneasy hybrid of wiggling sounds and ethnic effects. In "Safe Return", high-pitched strings fade in like birds elevating to the sky. "Emancipation" offers a hopeful yet sad melody offset by cracked percussion. The opening track "Shattered Skies" establishes the soundtrack's leitmotif, melding different melodic lines ingeniously. But the most impressive are the tracks that use wailing guitar to add spice to the soundtrack. In "Sitting Duck" the guitar creates a lively contrast to a glowing trumpet, while "Farbanti" boasts a killer guitar solo.

Some of the collaborators' compositions are just as masterful as Nakanishi's tracks. Keiki Kobayashi focuses on the orchestral aspect much more. In "Operation Bunker Shot", a bristling baseline and marching drums combine before a climax that introduces surprisingly powerful harps with loud cymbal and gong. It's a purely symphonic experience. He even brings in a mixed chorus in four voices in "Megalith -Agnus Dei-". This final stage track presents almost oppressive passion with absolute dignity. It's one of the most decisive-sounding and marvelous battle themes I've ever heard from any game.

Hiroshi Okubo's compositions are emphasized by strong percussive statements. "Lifeline" opens with a moody harp phrase that gradually brings in a stolid layer of strings beneath heavy, syncopated beats. "Breaking Arrows" accelerates midway through via ethnic percussion while deftly interweaving the leitmotif into some passages. The exception to Okubo's mostly kinetic works is the ending theme "Blue Skies", in which a cheerful guitar guides a mild piano at calm tempo, a soothing arrangement to accompany Stephanie Cooke's slinky, gentle vocals.

This acoustic feel is further progressed by Katsuro Tajima's "side story" tracks, which via live instrumentation establish a warm yet sorrowful atmosphere. Using an acoustic guitar duo, "Prelude" weaves a lamenting melody, while "The Bird Spread Its Wings" creates a slightly brighter sound. Both performances strike a sympathetic chord. The six tracks by Tajima give a subtle shading to the album's main component.

With only a couple of slightly dull exceptions, Ace Combat 04 Shattered Skies Original Soundtrack offers magnificent compositions and imaginative sound combinations. Make no mistake that at its core this is militaristic movie music, but its elaborate narrative quality befits independent listening just as well as it does its use within the game.