To say the Halifax, Nova Scotia co-ed quartet Dog Day has what may well be the quintessential, post-millennial indie-guitar-rock sound is to list the ways the band mines the previous two decades for influences. Dog Day’s spacious, atmospheric guitar sound easily recalls Echo & the Bunnymen’s epic gloom crossed with the dense swirl of early ‘90s shoegaze, occasionally interjected with moody Cure-esque synth lines and melodies sharpened with a Sonic Youth-like angularity. Of the two vocalists, Nancy Urich tends to sing with a likeness recalling Kim Gordon’s artless enthusiasm, while Seth Smith reaches for the fierce drama of Interpol’s Paul Banks, only to find his comparatively thin vocals fading seamlessly into the mix, a seeming liability. Instead, it combines smoothly with Urich’s in a way a more forceful singer’s could not. Concentration, the band’s second full-length release (following 2007s well-received Night Group) is 45 more minutes of this sound, certainly familiar but executed with undeniable passion and craft. If the album has any overriding flaw, it’s a bizarrely backhanded one: Poised at the record’s midpoint is the urgent, chiming “Rome”, a breathtakingly perfect Urich-lead pop song that threatens to render the rest of the album a failure for its inability to reach the same achingly melodic heights. Foundations have been shaken much harder than this.