It's hard to imagine a better homecoming than a performance at the world's largest music festival.

The Fatty Acids, a techno-infused rock band based in Milwaukee, topped off their American tour with the Sat. Nite Duets (who will also be performing at Summerfest on July 4) with an energetic show at the U.S. Cellular Connection Stage early Wednesday night. The opening day crowd, which respectably filled up about half of the stage's bench area, was more than eager to greet them back to Cream City.

The band, which formed in 2007, has grown wildly in popularity since their debut album, "Stop Berries, Berries and Berries, Berries," in June 2010. Since then, the Fatty Acids have not only been growing their name nationally with a robust tour (they noted in between songs that they had been potentially performing for 23 days straight), but also locally, where they've earned recognition and a few awards, including a 2011 88.9 Radio Milwaukee Music Award for Best Music Video.

After their performance Wednesday night, one could see where the praise was coming from.

The Fatty Acids started off their set with "Howl" and "Memory Banks," two energetic hits off of their first album. The two songs gave the group a chance to showcase some of the more unique elements of their sound, mainly a trumpet (played by Kurt Raether) and a beat machine, as well as their exuberant garage band-esque charisma.

Early, the variety of instruments created an unfortunately muddled blend of sound. Raether's trumpet was often lost in the mix, and lead singer Josh Evert's lyrics turned into an incomprehensible, yet pleasant sounding, blur of noise.

After some quick tweaks, the Fatty Acids songs quickly became audio gold, starting with the third song, "Astrovan." The song featured the group's lively energy while also showing off their musical skill, unhindered by muddled audio.

The biggest beneficiary of the perfected audio was Evert, who will never be confused for a lazy performer. The man played the piano and the beat machine while singing into one mic and occasionally two, one of which needed to be held. At one point, he stuck one of the microphones into his mouth, perhaps for an interesting musical effect or possibly just out of rushed necessity. Evert's joyously bouncy beat machine solo in "Astrovan" was easily the highlight of the song.

While less showy than Evert's rapid-fire solo, the second half of the show created some surprisingly beautiful and rich music. The end of "Marks We Leave" dissolved into an almost mournful trumpet breakdown, layered on top of the echoing guitars, piano and lyrics. Several of The Fatty Acids' later numbers built on the soaring instrumental harmonies to ear-pleasing effect. It almost seems like the group is an experimental electronic band, such as Animal Collective or MGMT, disguised as a garage band.

The Fatty Acids' approximately 30-minute set ended suddenly, yet satisfyingly, with "Hiroshima."

The young group has some places in which they can grow as performers; it would have been nice if the audio started off as clean-sounding as it ended up, and they surprisingly interacted very little with the hometown crowd, though that may have been due to time restrictions.

If they fix those tiny flaws and keep developing their fascinating sound, however, The Fatty Acids may be leaving town on far-reaching tours a lot more often.