An Unexpected Journey, and a still-reasonable effort on The Desolation of Smaug, stumbles at the finish line.
The big problem with the score is its lazy reliance on the material established in Shore's five prior Tolkien film scores. Not on specific leitmotifs, mind you; a bit more of that might have actually been welcome. (For example, Shore's themes for Hobbits and the One Ring, established in the original trilogy, make only a few brief appearances.) Instead, much of the music for The Battle of the Five Armies leans on established chords in established keys, without actually finding any melodies to lift them from an often-bland symphonic swamp.
There are moments of interest, here and there, but they rarely last for more than 4 to 8 measures amid otherwise mediocre tracks. The aftermath of Smaug's attack, for example (in "Shores of the Long Lake") seems to make a point of not taking an emotional view at a time the music ought to do exactly that. Are the people of Dale sad at their loss? Happy to have at least survived? The music doesn't want to say, nor does it convey a convincing blend of the two.
Smaug's faintly Middle Eastern theme, introduced in the prior film, is interesting for a while -- in tracks like "Fire and Water" (where it represents the dragon himself) and "Mithril" (where it personifies the corruption of Thorin). But in perhaps a reflection of how long the movie holes up under the Lonely Mountain without much actually happening, Shore runs out of ways to reinterpret that theme in interesting ways.
Fortunately, the battle material itself is more compelling. And as the movie devolves into what feels like an hour-long action sequence, there is at least a fair amount of that kind of music once you've made it through the first half of the soundtrack. "Bred for War" is an attention grabber where different sections of the orchestra seem to engage in a shouting match with each other, building a wonderful din of menace. "Battle of the Mountain" is full of energy, particularly in its bombastic final minute. "Ravenhill" is the all-out pinnacle of the album; the brass virtually scream at the listener, relenting only when the choir steps in.
Actually, it's the use of choir -- throughout the score -- that is the best thing about Shore's work on this film. He plays a lot with the different feelings evoked by male and female voices, from the bass martial cadences of "Sons of Durin" to the apocalyptic creepiness of sopranos in "To the Death." There's also some fun experimentation in the one new theme he creates for this final film, "Ironfoot." No doubt inspired by the casting of Billy Connelly in the role, the character's theme has a distinctly Scottish flavor. In the film itself, I actually found it a jarring break of the fourth wall, in how strongly it evoked a Braveheart vibe. But listening to the music in isolation, I find it to be some of the most inspired work of the soundtrack.
I'm not as moved by "The Last Goodbye," this film's end credits song. Billy Boyd, who played Pippin in The Lord of the Rings trilogy, sings the vocals. But the way it's all crafted feels like it's trying too hard to trade on fond memories of a great sequence in a far better film -- The Return of the King. When Pippin sang in that movie (as Denethor stuffed his face and soldiers perished), it was a haunting and jarring scene. Here the song is inert, trying to express a vague melancholy about the journey's end. I imagine that sentiment was felt by the people who worked on the films, but few audience members actually did.
In all, I'd say The Battle of the Five Armies soundtrack rates an average C. There is a sprinkling of standout moments, but most of it feels like music you already own if you own any of Shore's previous Lord of the Rings or Hobbit soundtracks.