On May 25, the new PDXchange Program concert series dipped its toe into Bend's live-music pool with a show at the Tower Theatre by Portland's Horse Feathers and local gals the Sweet Harlots.

From my perspective, it went off without a hitch; you can read my much more detailed review by searching “Westfall” at the Frequency blog.

It was a terrific night, but again, it was a toe-dip. I'm certain it didn't feel much like a toe-dip to PDXchange founder Henry Abel, who's put a lot of time, sweat and dough into booking Portland-based indie-rock bands at one of Bend's better listening spaces, but that's what it was.

On the other hand, PDXchange jumped in with both feet on June 3, bringing high-profile Portland duo The Helio Sequence to the Tower, and pairing them with local openers the Empty Space Orchestra.

And I think it's safe to say that Abel made the kind of splash he wanted.

As on May 25, the theater wasn't packed, though there were more people in attendance than there were for Horse Feathers. That's no surprise; The Helio Sequence is a solid, established name in its world, whereas Horse Feathers' profile is still rising. And Empty Space has lots of fans in town, which no doubt helped the second show's numbers.

But there was a strong buzz at the Tower on June 3 that wasn't quite as palpable on May 25. And it wasn't the buzz of a couple of young, contemporary rock bands' amplifiers, but the buzz of hundreds of folks excited to see what a couple of young, contemporary rock bands can do at Bend's historic downtown theater.

Certainly there have been rock bands at the Tower before. Dweezil Zappa Plays Zappa comes to mind, as does local band Tentareign's CD-release show in 2008. But I'm not sure the place has hosted a band as currently well-known, respected and, well, hip as The Helio Sequence, at least in recent memory.

But first things first: When Empty Space took the stage, I was surprised not so much by their new matching jumpsuits, but by the realization that I hadn't seen the band in months. In fact, I don't think I've seen them live since saxophonist Graham Jacobs rejoined the lineup after a year in Costa Rica.

Jacobs immediately made his presence known, kicking off “Brainjar” with the frenetic sax riff that sends the song on its labyrinthine way. His presence was more subtly felt throughout the set, too. During ESO's sudden rise last summer, their live shows were filled with slow-burn bursts of crushing, groove-heavy rock. Last week, they seemed to favor their jazzy, proggy, experimental side, where songs and time signatures shift with unsettling precision and speed.

Today's ESO is still a very, very good band, though I'm not sure it's quite as accessible as it was last year. Then again, having gotten to know those guys (and gal) over the past couple years, I'm pretty sure they're not too worried about being accessible.

What they did do, though, was draw curious folks down to the open area in front of the stage, where Abel removed three rows of chairs to create standing room low enough so as to not block views from the seats. A few brave souls wandered into the open area, but most were wallflowers until Brandon Summers and Benjamin Weikel — aka The Helio Sequence — slinked through the shadows and onto the stage.

This was the second time I've seen Helio, and my feeling today is the same as it was when I saw them two years ago: The wall of sound these guys make, using drums, guitars, effects and pre-recorded bloops and whooshes, is one of indie-rock's best-kept secrets.

The band's records are wonderful, warm baths of electro-indie-pop, equal parts organic and synthetic. Summers' voice is honeyed, and his melodies float like cotton-candy clouds. And Weikel is a machine on the drums, not literally, of course — don't you hate it when people misuse literally? — but his rhythm seems metronomic, and he looks animatronic as he works.

Helio's set list stuck mostly to the band's excellent 2008 album “Keep Your Eyes Ahead,” though they sprinkled in the best bits from 2004's “Love and Distance.” The set was nicely paced, ramping up from a relaxed beginning to a second-half stretch that included some of the band's very best songs.

Of particular note was “Everyone Knows Everyone,” a buoyant tune about living in a town with a tight-knit music scene, and the title track from “Keep Your Eyes Ahead,” with its needle-sharp, high-pitched guitar licks that would sound quite cozy on just about any Modest Mouse song.

Summers and Weikel closed their set with the roiling melancholy of “Lately” (as a perfectly psychedelic light show shone behind them) and “Hallelujah” before calling ESO drummer Lindsey Elias onto the stage for “Harmonica Song.”

It is exactly this kind of close collaboration that Abel wants out of PDXchange, where local musicians have a chance to play the Tower and to work with Portland's best. One day, he hopes, the exchange can benefit Bend's best by creating gig opportunities on the other side of the mountains.

Of course, it'll take strong performances by locals to make that dream a reality, and Elias was up to the challenge, helping to turn what's already a pounding tune into a serious gut-buster. Anyone who's seen her drum knows she's a beast behind the kit, so it was no surprise, but it was a legitimate smile-making moment watching her play with the Helio fellas.

And as she and Weikel wailed, Elias' hometown fans cheered and danced and stomped their feet to the beat, blissfully enveloped in the sound and PDXchange's promise of more great things to come.