At the forefront in the early days of “post-rock” was the Montreal ensemble Godspeed You! Black Emperor. They expanded the genre's definition from glitchy, minimalist post-punk with their poignant (and powerful) neo-classical string compositions in the late 90s. The group generated more than a few releases and spun off into a handful of side projects under the spacey canopy of label/collective Constellation Records, before imploding (exploding?) in 2003. Come on, you try to hold together a band of nine anarchists.

One of the side projects was Thee Silver Mt. Zion (formerly A Silver Mt. Zion/Tra La La Band), originally a trio of Godspeed expats which has since expanded into its current quintet state. Led by guitarist Efrim Menuck, the group weaves moving, impressionistic pieces that often transgress into darkness and lament. TSMZ eschews the idea of “lead singer” in favor of a “vocals as instruments” approach, though the sound is more concise than its collaborative and expansive progenitor. You would behoove yourself to check them out at Soundlab tonight (110 Pearl St., $12, 9pm).