When The System Lights takes the stage at the Y-Not III Sunday night alongside special guests Alex Vucelich and Penny Mouth, it’ll be a debut of sorts for the five-piece Milwaukee-based rock band. The only odd thing: The band’s been around for years already. In fact, they’ve even released a five-song EP, "Bright Water and Backroad Trips."

"Up until now, The System Lights has been a studio project," said David Rangel, the frontman, lead vocalist and writer for the band. "It really didn’t start out as a group. It was really started off as two people just wanting to get together some music and put it out there for the enjoyment of putting out art."

That was 2010. At the beginning, it was just Rangel and an old high school guitarist friend, playing and recording some songs Rangel wasn’t able to use in his previous bands. At first, Rangel – now a father and a bit tired of the touring side of the music business – had no interest in starting up a proper band. However, as they regularly kept playing together, the passion began to grow yet again.

"If that’s what’s in you – in your blood and soul – it’s hard to stay away from it," Rangel said.

From that point on, Rangel started searching out members for a full five-piece rock outfit. However, it wasn’t an easy search. Some had personal matters that kept them from committing to The System Lights; others weren’t the right fit for where the band was hoping to go. It took a while, but eventually Rangel unexpectedly found his second band member in Jim "Slim" Jacobs at a 2012 Pablove Concert at Turner Hall.

"I met him a years previously when he was originally looking for band members," Jacobs recalled. "It just didn’t work out timing wise; I was busy with a project at the time, a little too busy to really step in and help with songwriting. At this stage, though, I was actively looking for bands. So when I bumped into David, I made it a point to shake his hand. It took that nice little twist: David and Wendy (Sobczyk, the band’s business manager) were networking and looking for lead guitarists. The concert’s over, they’re kind of heading out for the night and I just happened to say hello."

The two ended up hitting it off, becoming the core members of The System Lights.

While hunting down three more members, Rangel and Jacobs have worked on perfecting the songs off "Bright Water and Backroad Trips" – which despite finishing recording back in 2013, was only released this past January – as well as further developing their sound, a mix of American and British atmospheric rock with lyrical references ranging from Los Angeles to Jack Kerouac, in various acoustic shows around town.

They’ve even managed to record some material for a new album. Six tunes are already recorded with four more, according to Jacobs, hopefully recorded soon.

"Both Slim and I have a vision of putting out music that is timeless, that can be listened to now or ten years from now, and it won’t sound dated," Rangel said. "We really try to stay clear of gimmickry or fads. Ultimately, I would like people to listen to what we’re doing now in ten years and still think, ‘Wow, this is pretty cool.’"

Nobody can say what’ll be the case in a decade, but right now, The System Lights' brand of rock has already gathered some fans. Thanks to their use of iTunes, Reverb Nation and other music-focused social networking sites, "Bright Water and Backroad Trips" has received some radio play on stations nationally and internationally – even as far as Ecuador, Indonesia and beyond.

Even so, their current mission hits a bit closer to home. In recent months, Rangel and Jacobs have finally found their final three members: second guitarist Russ Spice, bassist John Schneider and drummer Erik Byhardt. With the band all together, rehearsed and ready to go, and five shows set up throughout the city during the summer, The System Lights are finally ready to take the home stage and say hello.

"We’re kind of introducing ourselves to Milwaukee," Jacobs said.