4.5 out of 5

It almost happened. The ever-changing musical amoeba now known as East of the Wall almost released two records with the same lineup. But once again, change remains the most reliable constant for the New Jersey collective that for the purpose of brevity we’ll say falls under the umbrella of progressive metal.

NP-Complete marks the first album the band has written as a four-piece since 2010’s Ressentiment, a bit of trivia that probably deserves an asterisk since that record was originally intended to be put out under the short-lived Biclops moniker prior to its merging with a then-instrumental East Of The Wall. In any case, after a few more genealogical twists and turns, this latest offering was written by the remaining four members following the departure of guitarist Ray Suhy (now with Six Feet Under, Cannabis Corpse and a growing handful of side projects). In the absence of the Berklee-trained shredder who had been with East Of The Wall for one album and a couple of tours, the band retooled their sound yet again and each of its four members stepped up his performance to explore the space previously occupied by their insanely skilled former third guitarist. (Guitarist Matt Keys of A Fucking Elephant has since joined the band, rounding out its live lineup.)

As with each previous release, these tweaks to the chemistry resulted in East Of The Wall covering a range of new sonic territory, while still preserving the band's unique identity and establishing this latest album's unique identity within their catalogue. Generally speaking, NP-Complete is among their least aggressive records. While there is no shortage of mathy, angular riffage and maddeningly elaborate drumming, the album takes an overall more subdued approach, placing melody, texture, and well-developed song structures at its core. There are long, jammy parts reminiscent of latter-day Isis, albeit with a far more interesting rhythm section. Synths and harmonized trumpet lines fill out the mix in places. Bassist Chris Alfano’s screamed vocals, a staple of the band’s sound since its antecedent project The Postman Syndrome, don’t make an appearance until the third track, and then only sporadically throughout the rest of the record. Considering that they drove nearly every track on the previous release, 2013’s Redaction Artifacts, this is perhaps the most immediately noticeable change, and for longtime fans maybe a jarring one. But the restrained use of screams serves to highlight the contrast between the heavier sections where they do show up and the melancholy baseline of the record. And given the excellent performances by singers Greg Kuter and Matt Lupo, both more prominent here, it’s an adjustment that works.

Kuter plays a more significant role throughout the album, both vocally and in terms of the writing, and his decidedly non-metal background informs the songs to a degree not seen in his debut with Redaction Artifacts. As explained in a recent interview, closing track “Non-Functional Harmony” began with a rough arrangement originally meant for the singer-songwriter’s solo work, which the other members proceeded to take apart and transform into a sprawling 8-minute prog-metal epic. While the finished product is the most stylistically wide-ranging track on the album, its foundation is built on a relatively simple, almost bluesy guitar shuffle with an uncommon-for-them verse-chorus arrangement that shows off Kuter’s songwriting chops and stands out as a prime example of the band’s evolving chemistry. It’s easily the best song on the album, and arguably one of the best they've written. It also features some of the most straightforward, narrative lyrics the band has ever penned, from the perspective of a jaded musician whose talents go unappreciated until they finally decide to hang it up. Given how many players have come and gone in this project’s lifetime, it’s strikingly autobiographical for a band that has long made dense, abstract poetry its lyrical stock in trade. One hopes they’re not trying to tell us something. Then again, there’s also a pretty intense song on here called “Fast-Bang Pooper Doop,” so it’s really anyone’s guess as to when they’re actually being serious.

Someone who has followed the band’s trajectory over the past decade-plus can’t help but note the similarities between this latest configuration and the last time they went down to a four-piece, their early lineup change in which The Postman Syndrome became Day Without Dawn. As with that previous incarnation’s stellar full-length, Understanding Consequences, NP-Complete plays up its clean vocals, prominent and busy bass work, compelling guitar interplay, and focus on atmosphere. That’s not to say this album is a rehashing of that period—there are quite a few new twists on the formula, including the more extensive use of synths, more frequent and complex harmonized vocals, and the aforementioned tightness of the songwriting. Ultimately it’s still more of a metal record than Consequences was, despite the more restrained use of Alfano’s growls. But the color of it is not that different, something very welcome to those of us who still see Consequences as a, if not the, pinnacle of the collective’s work.

This type of stylistic shift toward the more progressive, moody, subtle end of the modern metal spectrum is not uncommon—see the evolution of The Contortionist or Intronaut, or to go back further, Cynic or Cave In. However, East Of The Wall and its related projects have put their unique stamp on it. They've wandered all over the stylistic map and found themselves in this general region twice, while sacrificing none of the interesting and unorthodox technicality of their heavier iterations. Yes, NP-Complete features the occasional catchy vocal hook or soaring guitar melody, but none of them come off as trite or lazy. There are no anthemic cliches here. With the exception of what could be construed choruses during “Lienholder” and the first half “Non-Functional Harmony,” the song structures are generally linear and ideas seldom repeat. The band keeps its big melodic sections unpredictable, challenging, and fleeting, a skill they have honed over their many name and lineup changes, and one that encourages repeat listens. Despite each lineup offering a slightly different flavor of the technique, it’s one that they continue to refine and one that keeps paying off.

If there’s a complaint to be made against NP-Complete it’s largely a positive one. At eight tracks and about 50 minutes, it’s one of the band’s shorter records. After six years it would have been nice to hear a little more new material. But to East Of The Wall's credit, what they chose to include in this breaking of their silence feels more consistent, purposeful and...well...complete than anything we’ve heard from them in a long time.