More often than not, festivals connected to big commercial radio stations—particularly alternative stations—parade a combination of mediocre major-label rock bands desperate for airplay and one-hit wonders desperate to make it two in front of crowds not really in search of much more. Good timing and left-field hits for two long-running bands made the second day of Chicago’s Q101 Block Party a glowing exception to the rule, as tourmates Modest Mouse and the Walkmen were joined by fly-in guests Death Cab For Cutie in an indie-rock cream-dream triple decker. (For a colorful juxtaposition on what “summer alternarock radio festival” usually means, look no further than day one of this event, which featured the Presidents Of The United States Of America, Sponge and Local H.)

The Walkmen passed the ultimate test for a dark-clad, trebly New York band: They played right into the sunshine to more than 10,000 people that may know them only for a song that appeared on a car commercial, and they knocked at least a few of those people out. Eyes on guitarist Paul Maroon, bassist Pete Bauer or organ player Walter Martin got admirably stock-still business, while those attached to singer Hamilton Leithauser or drummer Matt Barrick found more intensity. Barrick could barely stay in his chair, and the lanky Leithauser nearly lost his balance with every shout. The sun still blazed as they roared through ace single “The Rat” and Saturn-assisted slow-burner “We’ve Been Had,” but the Walkmen made it feel dark and smoky.

Death Cab For Cutie couldn’t match that Walkmen muscle, but then again, it’s not really trying to. Though fresh off a day-long journey to Chicago (the band played Portland, Ore., the night before and flew out for this one-off), Death Cab showed off the chops and confidence that follow a banner year of success and touring. After an introduction by morning DJ Mancow (who, in his own sub-Stern way, professed a love for the band), Death Cab plowed through a career-spanning set, from the semi-obscure “Photobooth” to the crowd-surf-inspiring “Sound Of Settling” to the rapturous set ender “Transatlanticism.” Those who find the band’s records too squishy may be shocked by the rollick of Death Cab’s often-astounding live show.

Modest Mouse can’t be the biggest little band in the world anymore, since “Float On” has pushed Good News For People Who Love Bad News near platinum. Shockingly, though, the kids assembled at the front knew the words not only to the hit single but to the deep cuts, too, including scratchier, harsher songs of yore like “Doin’ The Cockroach.” Digging through the band’s catalog, you could assemble an incredibly difficult-to-love set, but for the past few tours, Modest Mouse has delivered set lists that would make an unstoppable greatest-hits package, from “Interstate 8” and career pinnacle “Never Ending Math Equation” to “Paper Thin Walls” and “Third Planet.” As jaded and pessimistic as his lyrics can be, singer/guitarist Isaac Brock delivered his songs with a ferociousness that hovers between magnetic and scary. After a gentle reading of “The World At Large” on electric piano, Brock and Co. charged through a jammed-out “Cowboy Dan,” driving together their opposite sides toward one of those cataclysmic rock moments that can’t be denied—even at an alternative-rock radio festival.