Megz Tillman, right, of Magna Carda joins Keeper at ACL Fest on Friday, Oct. 7, 2016. Peter Blackstock/American-Statesman

Early in the day at the Austin City Limits Music Festival stresses the “Austin Music” part of that title. Just before and after noon, we caught two locals on adjacent stages who provided an intriguing study in contrast.

At 11:30 a.m. on the Miller Lite Stage, our October Austin360 Artist of the Month, Keeper, made its ACL Fest debut. Featuring vocal harmonies from Yadira Brown, Erin Jantzen and Kate Priestly, with a DJ behind them sampling beats, synths and bass lines, the group is a case study of the new Austin, related not at all to the rootsy outlaw-country sounds that put the city on the musical map decades ago.

Their youth and newness proved both an asset and a burden in their 35-minute set on what was almost certainly the largest stage they’ve ever played. There were obstacles to overcome, most notably sound bleed from the Cirrus Logic stage across the field that caused some problems early on. Perhaps to compensate, the bass was turned up loud enough in Keeper’s mix to obscure some of the magic of their vocal harmonies.

But they kept at it, with both the band and the sound crew getting better as they went along. Later songs pushed keyboard samples more prominently the fore, while creatively off-kilter beats and rhythm tracks pushed the songs toward adventurous territory beyond the simple notion of three complementary voices playing off each other.

“We’ve got some work to do,” they sang out in the last line of the next-to-last song, a fitting acknowledgment that Keeper has a long life of musical challenges and opportunities on the horizon. But they also had a big milestone to celebrate, and they did that on a hip-hop-infused finale that features a guest appearance by Megz Tillman of our February Austin360 Artist of the Month, Magna Carda.

Asleep at the Wheel plays its 15th ACL Fest on Friday, Oct. 7, 2016. Peter Blackstock/American-Statesman

A few minutes later, the even-larger Honda Stage cranked up to the firing-on-all-cylinders sounds of Asleep at the Wheel, the only band to have played all 15 years of ACL Fest. They’ve had plenty of practice in making sure the sonic balance of their eight-member lineup is just right — not just from their long history here, but from leader Ray Benson’s decades of experience before that. The Wheel is the embodiment of a well-oiled machine.

Still, there’s something new going on with them, too. Dozens of backing members have cycled through Benson’s lineup since the 1970s, and every once in a while, a clear star-in-the-making rises from the chorus of guitar, piano, horns, strings and steel. At present, that protege is Katie Shore, who last month released her first solo album, and has increasingly become almost as important to the current Wheel’s identity as Benson himself.

Thus, as old-school as Asleep at the Wheel may be — the lone down side to their exquisite professionalism is that, unlike Forrest’s box of chocolates, you pretty much know what you’re going to get every time with this crew — youth still is served when these bright new faces come along. Whether she was trading sassy vocal lines with Benson on “I Hear You Talkin’,” burning up her fretboard on the intro to “Tiger Rag,” or getting her own turn in the spotlight for her solo album track “Goin’ Up a Hill,” Shore was a primary presence.

And so, on the stages of Zilker Park, as in the streets of downtown, old and new Austin proceed forward, side by side. At ACL Fest, Keeper keeps on keeping on, and the Wheel keeps on turning.