He checks off all the boxes as a multi-talented musician, producer, and studio owner. While he's known for his early career days as a drummer with A Flock of Seagulls and Canadian rock band, Alias, these days, Marquart is focused on his current project, A Bad Think. Recently, the Los Angeles-based band was honored with a GRAMMY® nomination for the album The Savior in the category of Best Immersive Audio Album.

In the mid-2000s, Marquart founded A Bad Think, which he writes, records, and produces music for almost entirely by himself. "The name came from my kids. They would come down in the middle of the night, they would go, 'Dad, I can't sleep. I had a bad think,' so my kids are the ones that actually came up with that name. I play most everything on there, but I always get other people to play on it, like a bass player, or I get my daughter Samantha to sing on it sometimes. We're going to get some great people to work on the new [album], but it's really me."

Currently recording A Bad Think's ninth studio album, Marquart spends most of his days working out of his personal studio, The Barn, located in Malibu, California. "This is where I work day in and day out. It's a really special place," he says. And, special seems like an understatement considering all of the wood used for the design was salvaged material from the original Hollywood Bowl during its remodel a few years back. Peter Grueneisen, who designed The Barn, won a NAMM TEC Award for the studio design. Now, while Marquart works, he can feel the magic the wood previously absorbed from Hollywood legends like Frank Sinatra, Dean Martin, The Red Hot Chili Peppers, and Elton John, to name a few. "It's a special place⁠—you feel it. I come down here and work every day, and I have a studio in Virginia Beach. Every day, 365 days, I'm in there working."

As if that doesn't make him busy enough, Marquart is also the founder and owner of a world-class recording facility, Windmark Recording, based in Santa Monica. The studio was formerly owned and built by Jimmy Jam and Terry Lewis, who sold it to Marquart. After relaunching five studios, Marquart designed Studio F on the ground floor. "That was gonna be my room, so everything in there is kind of how I wanted it. But when the studio was done, all these clients wanted to get in there, so I said okay and kind of relinquished command of that studio" he explains. The entire studio is frequently completely booked to many notable artists, including Coldplay, Jeezy, J. Cole, YG, Kanye West, and Kendrick Lamar. He credits his daughter, Samantha, who manages the studio and his son, Mikey, who helps with day to day operations for its success.

When it comes to reflecting on his early days running a business, Marquart can still remember the original Windmark Recording Studio, originally based in Virginia Beach. "My first studio was a little 4-track reel-to-reel Tascam, and you know, recording in the basement," he remembers of the business he ran alongside Bill Reid. The latter was president of Cellar Door, a large concert promotion business at the time. Together, the two would find artists, produce records, and put them out on tour, almost like a conveyor belt, until Reid left that company. Not before the studio expanded, however. "So there I am, you know, stuck in Virginia Beach with a world-class recording studio," Marquart laughs. Luckily, it all worked out. "I started working with The Neptunes (a duo composed of Pharrell Williams and Chad Hugo); they're local Virginia Beach guys. Serban Ghenea, who was the top mixing guy, was in my studio B, so he was doing a lot of mixes for these guys, Britney Spears, all that kind of stuff. So they started coming in and next thing you know, they're kind of there all the time. So, I wound up selling the studio to The Neptunes."

These days, much of Marquart's time is spent at The Barn, striving to write better songs and make better records not to lose his creativity. "My recording process works like this—if I'm working, sitting outside with my guitar, my lyric book, and if I get an idea, I kind of work the idea. I come down here, start laying it down. It starts with a simple guitar track, and it just slowly starts to build. I don't try to run it down a certain road. I just do what kind of happens, and when the album is done, then it gets released."

Behind the scenes in the studio, Marquart has an extensive collection of guitars he admires. "I have favorite guitars, I have some that I always use on my records, and I have some I always use for doubles," he explains, pointing out particular favorites including a 58 Gibson Burst, a 1950 Fender Broadcaster, a 54 Fender Stratocaster, a 58 Fender Jazzmaster in blonde, and several acoustic guitars. "Fender did a limited run of guitars called Front Row Series, and they were kind enough to make me one which I begged them for, and they were very kind to do that. So, I don't know how many they actually made, but it's a great guitar, and I was lucky to get one. But, I have a go-to thing, like a 62 Les Paul that looks like an SG. I have this acoustic guitar that Martin made for me, that's my new favorite guy."

When it comes to recording guitar, no matter which studio he records in, Marquart prefers Neumann mics. “It’s kind of different here [at The Barn] because I have the [Neumann] U 47 here, and I have a jeweled [Neumann] M 49 on the East Coast that I used for acoustic guitars. I have the same vocal chain, they’re exactly the same, so that’s no problem. But, I do like recording acoustic guitars.”