Review Summary: A wonderful soundtrack, whether you're a fan of Mega Man or not.
The early Mega Man games have garnered a reputation over the years as some of the most beloved and most addicting 2D action games of their eras, particularly the first five or so games in the original series and (arguably) the first five or so X games. While developer Capcom have been ridiculed time and time again for milking their franchises for a quick buck, the sales prove that many gamers wanted more of the same from each series and subseries. Now between Battle Network, Zero, Star Force, and a whole slew of other spin-offs, the Mega Man franchise has gone out of control in terms of products; however, let's remember where the series came from: fun, side-scrolling action. It should be no wonder that the music certainly played a big role in these games as well, not just from a "heart-pumping battle theme" standpoint, but even an emotional standpoint as well. The fortress theme from Mega Man 2 is still a highly melodic and reflective listen as you're heading to Dr. Wily's HQ, despite the high tempo and power metal-esque vibe. Then there's the Frost Walrus theme in Mega Man X4 which sounds as icy and cold as the name of the aforementioned boss.
Basically, the charm of the Mega Man soundtracks is that they effectively combine high-speed intensity with a real sense of atmosphere. Particularly once the PS1 era of the series came into effect and the sound quality was improved, games like Mega Man X4 and X5 utilized the new technology to create more vivid atmospheres and more detailed compositions. However, X5 has to be a candidate for having the best soundtrack out of any Mega Man game. Why? Because it's a perfectly balanced piece of work for a game that was originally meant to close out the series. You get a mix of high-energy power metal instrumentals, piano and synth-based ballads, and even some progressive rock moments here and there. Composers Naoto Tanaka, Naoya Kamisaka, and Takuya Miyawaki created a more moody experience than in previous games in the series (with the possible exception of X4), befitting of the more emotionally resonant turn the X games had taken by this point. However, those moments of fury and heaviness still come out in full force; the themes for the both the Sigma and Dynamo boss fights are some of the fastest and most guitar-driven songs in the franchise, made even more memorable by the bold synthesizers on top of the tracks. There are also new experiments this time around such as the theme to the last Sigma battle, an epic string-driven number filled with trumpets and thunderous drumming. There are also shorter songs placed to break up these moments, such as both X and Zero's thrashy-yet-melodic "Stage Clear" themes.
But indeed, the best aspect of this soundtrack is its ability to balance aggression and introspection into a near-perfect whole. The reason it works so perfectly is the fact that it mirrors the game's tone and feel so well; the moment that X's companion Zero dies, the funeral-like theme that plays during the touching moment is absolutely gut-wrenching, despite being a simplistic display of melancholy. Some songs, such as the "Zero Theme 1" and the Shadow Devil theme are pretty bizarre when compared to the rest of the soundtrack, but the former works because of the fascinating sense of wonder in its unusual synth arrangement while the latter works because its high-pitched organ playing heightens the tension of the battle it's featured in.
Honestly, when you get down to it, the power of these songs comes from the moods they create, whether in-game or not. This soundtrack's sense of atmosphere is killer, and the way these songs are composed assure you that there's something for any mood you're in. And when you hear the theme of the end credits at the very end, or see them after defeating Sigma at 5 in the morning, there's a sense of reflection not normally found in games or games' soundtracks in the side-scrolling action genre. The somber and haunting piano theme eases its way in, and you remember all those memories you shared with some of the most thrilling and emotional games... some of them may have lost their popularity or relevance along the way, but they still make their way to the heart nonetheless. And that's like this soundtrack... it may be to a slightly dated PS1 game that has lost its popularity to a degree, but its charm will stick with you and last for ages.