Coming off the underground success of their previous album, “Alive or Just Breathing,” Killswitch Engage have released a follow-up that should only solidify their reputation as one of heavy music’s top young bands. These guys were already established as a leading band in the crowded melodic hardcore genre, and “The End of Heartache” sees their sound becoming even more focused and diverse. While still a notch below the truly great heavy bands like Burnt By The Sun, the Dillinger Escape Plan, and Meshuggah, KSE are definitely on their way up. Three albums into their career, they may well be peaking right now.What’s most impressive about this album is just how tightly written and played it is. Every song is calculated for maximum visceral and emotional impact, with the band deftly exploiting dynamics as they careen back and forth between balls-out aggression and soaring melodies. Yes, there are plenty of bands in the metal/hardcore/metalcore/whatever genre doing that right now, but KSE are still notable for the emotion, creativity, and musicianship they bring to the genre. Adam Dutkiewicz and Joel Stroetzel lead the charge with a devastating two-guitar assault, cranking out some complex and interesting riff structures without sacrificing the intensity that’s at the core of the band’s sound. Howard Jones also deserves a great deal of credit, stepping in on vocals for the departed Jesse Leach without missing a beat and somehow managing to raise the emotional stakes even higher than his predecessor. Howard’s screams are more jarring, and his clean singing clearer, making him a perfect match for the band’s unpredictable, wide-ranging sound. Throw in a pile-driving rhythm section, and you’ve got a band that’s getting very good at combining power with polish. While KSE may not be the most original band out there, they do show quite a knack for combining the sounds of those who came before them. While there is plenty of uncompromising hardcore stomp on display, much of “The End of Heartache” sees KSE expanding their genre-bending approach. The opening “A Bid Farewell” packs more sonic shifts into four minutes than many bands do on an entire album, starting out with some chunky, heavy rhythms before taking off at breakneck speed and then stopping dead in its tracks for a big, epic chorus. Alternating monstrous riffage and chugging basslines with hard-driving guitar harmonies, “Take This Oath” sounds sort of like Fear Factory crossbred with In Flames. The title track, featuring an abundance of singing and some slightly corny lost-love lyrics, may veer uncomfortably close to ballad territory for some, but it’s an undeniably powerful song whose melancholy mood is occasionally shattered by Howard’s piercing shrieks. There are a few nods to the old school to be found here, as well. “Rose of Sharyn” is reminiscent of Iron Maiden in its grand sweep, driven by some aggressive hooks and insanely catchy guitar interplay. The lightning-fast riffs and airtight double-bass drumming of “Declaration” show an ’80’s thrash influence, sort of like Metallica or Testament given a 21st-century update. And in something of a curveball, the tricky rhythms and abrupt time changes of “World Ablaze” see the band going in a more technical, “mathy” direction that could serve them very well on future albums. It’s not quite Meshuggah, but it’s a start. All in all, “The End of Heartache” is one immensely enjoyable album from a band that seems to be showing a real commitment to maturity and diversity. It’s good to see that heavy music’s recent resurgence hasn’t come to an end quite yet. If you want some metallic fury rocked with rage and intelligence, this is a good place to look. Come year-end, this album should wind up on more than a few “best-of” lists.