Barely a day after traveling from Moline, Ill., to Los Angeles to play the International Pop Overthrow festival, Kerry Tucker, guitarist for an outfit named Einstein's Sister, knew he had found his niche.

"We were in line to buy some of the other bands' stuff, when we realized the other guys were in line too, to buy our disc," Tucker said, recalling his show last summer at a Hollywood club. "It was like a family reunion of a family that had never met before."

That family reconvenes Friday, when the third annual IPO, a conflagration of more than 150 bands from points as distant as Europe, Japan, Australia and even Moline, launches the first of its 19 shows at 10 venues through Aug. 3.

The fraternal atmosphere that resonates through IPO shows gratifies its patriarch, David Bash, a 41-year-old business consultant and freelance writer for whom the event has become a rite of passion.

Toiling from his CD- and LP-filled Studio City apartment, Bash has emerged as a self-appointed crusader for a commercially impotent genre that has been shouted down by a cacophony of rap and hard-core as well as crowded out of the marketplace by slickly produced and heavily promoted teen acts.

"Pop as we know it is music that relies on melody and harmony, with prominent guitars," Bash said. "It's music that is strongly influenced by but doesn't necessarily sound like what we heard in the '60s and '70s."

Or, as Robbie Rist laughingly describes it, "the anathema of cool."

Rist, a former actor (he played cousin Oliver on television's "The Brady Bunch") who will perform with the Andersons and at least two other bands at IPO, said the event showcases material "that is a throwback to what's melodic and hooky . . . , songs that hit that G-spot in your brain."

The people who make those songs--from guitar-strumming troubadours to seemingly radio-ready power-popsters--rally around IPO, a sprawling affair that sprang three years ago from Poptopia, a festival for Southland bands. "I had an epiphany," said Bash, who helped with Poptopia. "It was 'Field of Dreams' thinking--if you hold it, bands will come."

And come they do, although there is no payday, although there are as many as eight or nine bands per bill, although sets routinely span only 30 minutes.

"It's summer camp for pop music freaks," said Johnny Norris, a 30-year-old Memphis attorney who, along with his Crash Into June bandmates, took vacation and made his first trip to L.A. last summer. For their trouble and travel expenses, the members of Crash Into June spent a couple of days as tourists, a few hours as fans and 30 minutes showing off their shimmering guitar work in front of a small crowd at Fitzgerald's Irish Pub in Huntington Beach.

'For the Love of the Music'

They begged Bash to be invited back. "It's no accident that bands are coming from all over the world to play [IPO] for no money," Norris said. "You do it purely for the love of the music."

Pete Kennedy, a former Nanci Griffith sideman who performs with his wife, Maura, as the Kennedys, scheduled IPO as one stop on a nationwide tour promoting their Byrds-influenced album "Evolver." He likened the festival to a convention. "A gathering of the clan," he said, "like people raise a certain kind of exotic dog."

"People like us are very fervent believers," Rist said.

The attraction of playing in Los Angeles fuels that passion, and the importance of that credential is not to be underestimated.

"I believe we are the first Austrian pop band ever to play in the U.S.," said Paul Reichel, bassist for the Salzburg foursome the See Saw. "It's a great opportunity for us--and gives us very good press [in Europe]."

The festival's value as a career springboard remains unproven, though Bash waxes optimistic that, by its sheer breadth and energy, IPO can "coalesce the international pop scene and overthrow conventional mainstream thinking, and show that there is an audience for this kind of music and that it will sell."

The chance that somebody might be buying provides incen- tive enough for many bands.

Take Chicago-based Big Hello, a band with an Elvis (drummer Brad), a Million (guitarist Johnny), an Orwell (sassy vocalist Chloe) and a raucous Go-Go's-meets-Cheap Trick sound. Its 1998 release "The Apple Album" earned good reviews, and a follow-up, "The Orange Album," was released this month on tiny Break Up! Records in Ohio.

"I'm not going to lie to you-- I want to sell lots of records and play big venues," Elvis said. "I don't go waving the pop banner, though for years I gave it a college try. It seems like calling yourself a pop band is a kiss of death.

"I just try to write memorable songs with great hooks and, hopefully, it sticks."

Elvis' "working vacation" approach--play a little, promote a lot--is shared by many bands. Big Hello, Crash Into June and many others--such as Spain's the Happy Losers--have scheduled other Southland shows for the trip. Many plan to make or rekindle music industry contacts.

Struggling for Recognition

But the reality is that getting the industry's attention is "hard as hell," said Robb Vallier.

A native Iowan who attended Berklee College of Music and has lived in Los Angeles for seven years, Vallier worked as a session musician before striking out on his own and forming a band called New Bitter Pop Stars. Band manager Chris Violette said there have been talks with record labels, but no deal.

"There are no Cinderella stories," said Vallier, who laughingly refers to himself as a "pop star in training."

But his joie de pop remains undiluted. "We're on an island," he said of the IPO crowd. "It's nice to meet the other castaways."

For Bash ("It was hard having that name growing up, but it kinda works now," he said), the success of International Pop Overthrow is measured in smiles as much as sales.

Named as a tribute to Chicago popsters Material Issue (whose seminal 1991 record carried the title), the festival features stalwarts such as Jellyfish/Grays frontman Jason Falkner, who is revered in IPO circles, as well as veteran acts such as the Rubinoos, the Innocents and the Greenberry Woods. The event is financed by gate receipts and sponsorships (mostly independent record labels), and Bash said attendance, though uneven, was "incredible" last year, including a sellout at the Troubadour show.

On show nights, each act receives an enthusiastic introduction from the organizer--in fact, Bash said one of his proudest moments ever was being able to introduce the band Shoes at last year's festival. In addition, there is an IPO compilation CD for the third consecutive year--a two-disc collection released by Not Lame Records, among the more prominent of the small labels that keep the heart of pop beating.

And nobody seems to find it too remarkable that the festival largely reflects the taste of one man.

"David can get a CD from a cornfield in Iowa, like it and be e-mailing an invitation the next day," said Gail George, the festival's marketing director.

Bash merely feels fortunate to have become the rare obsessive pop fan who has brought to life much of the music that lines his shelves.

"It's exhilarating," he said. "It's rewarding to bring people who love what they do to an audience who will appreciate it."

Kevin Bronson can be reached at kevin.bronson@latimes.com.