The Helio Sequence’s rise to prominence is an unlikely one. This is, after all, a band born in a Beaverton bedroom, fathered by two music geeks with a hard-core affinity for psychedelic ambience and cerebrally pulsating experimentation. But something happened during the band’s 13 years of life: the duo embraced light poppiness and a little folk, grounded itself in complex lyricism, and with the release of 2008’s excellent Keep Your Eyes Ahead, made real national waves. 

Helio’s hotly anticipated fifth album, Negotiations, reins the psychedelics in a bit. The staccato drums, heavy synth, and fluttering guitar hooks of singer/guitarist Brandon Summers and drummer/keyboardist Benjamin Weikel remain, but there’s something more organic to the sound this time: amid the robotics lies a bigger heart.

From the stutter-step march of the opening track, “One More Time,” to the hypnotic closing track, there’s a pronounced stress to Summers’s delivery, presumably the by-product of age and the extreme vocal strain that sidelined the singer prior to the recording of Keep Your Eyes Ahead. He actually sounds better and more human for the wear. On the morose “The Measure,” the strain gives life to a plea for understanding, as Sommers laments, like a hybrid of Thom Yorke and mid-career Bob Dylan, “So you want to know the difference/between the broken and the lost/ between the voiceless and the muted/ between the payback and the cost.”

Songs like “The Measure” follow a formula that has served Helio amazingly well over the past decade: start as sparks and end as explosions. But Negotiations also has its lulls. The twangy “Harvester of Souls” brings the kinetics of the record to a screeching halt with its rather standard-issue, acoustic lament. But the falter is momentary, as “Harvester” turns to “Open Letter,” where the driving drums and sense of discombobulation are nothing short of breathtaking. Percussion loops and rhythmic guitar progress like a heartbeat as subtle orchestral swells pique emotion in an almost cinematic way, pushing forward with the sense of purpose and necessity that “Harvester” misses.

The lulls are a small price to pay on a thoughtful album that runs the gamut of emotions, compiling every lesson, blip, bleep, soaring crescendo, and solemn valley Helio has traversed. The duo presents itself with a maturity that continues to snowball and solidify their sound, proving they’re still riding high on a wave that shows no sign of cresting.

The Helio Sequence will perform as part of MusicfestNW at the Crystal Ballroom on Sept 7.