Pete Townshend coined the term “power pop” in the 1960s to describe The Who, but the phrase was forgotten for more than a decade. In the late ’70s, rock critics began applying the pithy phrase to Big Star, The Plimsouls, The Last—bands recovering the endangered verities of mid-’60s rock in three-minute testimonials to melody and harmony, two guitars, bass and drums.

  Power pop never produced another Beatles but has survived as a handy marketing label for a genre of melodic rock. When one such band, Material Issue, recorded a song called “International Pop Overthrow” in the early ’90s, they intended it as an anthem for the music they loved. They had no idea their song title would become the name of a festival dedicated to power pop, first in Los Angeles and then, in recent years, in cities across the United States.

  This year, International Pop Overthrow comes to Milwaukee for the first time, May 1-4 at Linneman’s. Along with relative veterans Heathrow, relative newcomers Plexi 3 and reunions of Spill and Fun With Atoms, the bill includes a group that’s been MIA for the last year, Trolley. Although its members are dividing their lives between work, school and other bands, Trolley has an album in the can of spine-tingling songs that synthesize elements of The Kinks and The Beatles, among other influences. They hope to release it in the fall.

  Like many other DIY acts in the Internet era, Trolley has been unable to sustain a financially supportive career even as they acquired far-flung fans across the world. Power pop has proven to be a handy label, leading aficionados in Europe and elsewhere to purchase their back catalog of self-released CDs. On the other hand, power pop is a tight corset for a band that has incorporated punk, surf instrumentals and psychedelia into their repertoire of original, often ’60s-inspired songs.

  “A lot of what’s called power pop has a glossy sheen,” says guitarist-vocalist Paul Wall. “I like stuff that’s more off the cuff, with a few mistakes. Maybe I’m a punk rocker at heart.”

  Adds bassist-vocalist Terry Hackbarth, “A lot of power pop has lost the power. The first wave of power pop after Big Star, at the same time punk was happening, was pretty exciting.”

  Trolley is aware of the irony that power pop isn’t actually popular, but merely one niche among many in a musical world without a center of gravity. “I like to say we’re a rock ’n’ roll band,” Hackbarth says. Sadly, rock ’n’ roll is a word that sticks like Velcro to anything with guitars and drums. The power pop label may be valuable precisely because it is more specific, signifying catchy melodies, layered harmonies and concise songs.

  For its May 1 performance at Milwaukee’s International Pop Overthrow, Trolley will play new songs, tracks from the group’s previous album, Last Chance Dance, and, maybe, a ’60s cover.

  “It’ll be a fun night,” Wall says. “Very fast and quick-paced. If you don’t like one band, stick around for 20 minutes and you’ll hear another.”