The final day of Fun Fun Fun Fest 2015 was a chilly one. But that didn’t hold back the crowds for the last showcase hosted by Grammy Amplifier, a Hyundai Music Initiative, at the venue that used to be Red 7 on East 7th Street. The theme of the show — which began earlier than the listed set time because it was Sunday, after all — was pure rock. Easing the audience into the concert was pop-rock band Bonavox, who won last year’s competition. The group’s folksy anthems turned the venue into a mini-dance party. There was even a mashup of the slow “Voice of the Ocean,” with just vocals, acoustic guitar and plinky mandolin, and the high rolling sounds of “High and Low.”

Bonavox’s radio-friendly sounds led the way to harder rock acts with headbanging fanbases. Feral Future, Think No Think and Borzoi unleashed their walls of sounds. On the inside stage, Feral Future’s fearless and confrontational music filled the room as lead singer Relle whipped her hair around. Rozwell Kid were completely lost in their own attack of guitars. At one point, singer Jordan Hudkins amped up the crowd into responding “YES” after his howls of “HELL,” which reappeared during a song. He even invited the group’s biggest fan at the show to dance interpretively onstage.

Austin favorite A Giant Dog’s FFF Fest set was cut short due to rain delays, but they made up for it in their high energy penultimate slot at the Amplifier showcase. The punk band, which recently signed to Merge Records and will release a new album sometime in 2016, cranked things up with strutting singer Sabrina Ellis’ loud and powerful voice. Two dancers clad in gold swimsuits jumped on the stage during one song, and she whipped off her pants and jacket to reveal matching bottoms and a peacock feather bra top. The three danced in unison as the rest of the band played on for the rest of the set.

Lastly, poetically visceral group Speedy Ortiz, led by Sadie Dupuis, politely waited until A Giant Dog finished their indoor set. Then she and the rest of the razor sharp band, ended Fun Fun Fun Fest by embarking on their lyrically brilliant throwbacks to the ’90s.

The GRAMMY Amplifier program, which presented the showcase, is an online music initiative that aims to help promising music artists realize their dreams. The 2016 program’s curators — Big Sean, Halestorm’s Lzzy Hale and country singer Sam Hunt— will listen to submissions and select three winners. Those winners will each receive one of three prize packages: a studio recording session with a GRAMMY-winning producer; an opening slot for a noted artist and/or a series of festival shows; or the filming of a music video with a celebrated director.

Submissions for the 2016 GRAMMY Amplifier are now open, and you can upload your songs for consideration at www.grammyamplifier.com until January 4, 2016.