"I don’t know if nitrous oxide is dangerous,” reflects Steve Carton. “But it’s fucking explosive.”

“Right on,” I say, wondering what I’ve gotten myself into. It’s Tuesday afternoon in the service garage at Great Northern Stereo, a car-stereo Mecca about 3 miles south of downtown Burlington on Shelburne Road. Carton and his co-worker, Corey Oliver, are walking me around an otherworldly 2001 Acura Integra LS: five-color paint job, nitrous tanks, racing-harness seatbelts. The thing has a sound system big enough for several developing nations.

It’s easy to get annoyed when a car blows past you blasting beats — but I wanted to learn what’s behind the racket, and to discover what makes car stereo gurus tick. As it turns out, these particular tinkerers are anything but average specimens. When the baby-faced Carton, 20, and goateed Oliver, 22, talk about electronics specs, it’s as if they’re speaking a different language.

The two are full-time installers at Great Northern. In an average week, they outfit about 20 cars with custom stereo gear for between a hundred and a few thousand bucks per job. This includes custom audio equipment, but also iPod consoles and televisions. Put another way, Carton and Oliver could be responsible for more moving noise violations than any other duo in Vermont.

With matching black T-shirts and chains, Carton and Oliver look imposing, but in a goofy way — think Vanilla Ice at an ice-cream social. Their friend Brandon, 22, whose T-shirt reads “Speed Freak,” slurps a McDonald’s soda in the corner while my two guides show me around the auto, Vanna White-style.

Many of today’s cars come pre-outfitted with expensive sound systems. That means less custom work for specialty shops like Great Northern. But no auto maker could come close to Carton’s Acura. It’s fantasy material. He bought it for $7500 in 2005 and has since added about $12,000 worth of accessories, half of them entertainment-related. When he opens the back trunk, a 10-and-a-half-inch television screen pops down as testament to its owner’s outlandish pursuit of mobile delight.

Oliver, I learn, drives a custom ride of his own — a 1988 Honda CRX DX with a JDM SIR B16 A1 motor, shaved body moldings and DC Cat Back Exhaust. In other words, a matching illustration of aerodynamic egomania. Moreover, both men own “budget buggies” — commuter cars they use for slumming around town during inclement weather, or for engaging in such pedestrian activities as grocery shopping or going to the mall.

“How do girls react to it?” I ask.

Carton and Oliver smile at each other.

“Oh, yeah — chicks dig the car,” Carton asserts.

“Chicks love the car,” Oliver adds.

The Speed Demon slurps approvingly.

As we stand around ogling Carton’s car, he and Oliver begin listing all its specs in tandem, as if for the hundredth time, with a practiced domestic familiarity. Two Boston pro 6.5 speakers, one says. Kicker L7 12-inch subwoofer, adds the other. Monster cables. Upgraded deep-cycle battery. Strobes. Playstation.

“It’s untouchable,” Carton concludes.

“It’s got a lot of shit,” Oliver echoes.

For all their macho inclinations, I think, these ‘tough guys’ finish each other’s sentences like a pair of newlyweds.

And for all the chick magnetism of their cars, they admit that harboring a passion for wigged-out whips sometimes has unexpected consequences. Carton, who characterizes his car as a “sick obsession,” admits he recently lost a girlfriend over the Acura. “She wasn’t feelin’ it,” he laments.

“The car or the girlfriend,” Oliver chirps. “The car won.”

The way these guys explain it, a car-stereo fixation sounds a lot like a drug or gambling addiction. Both confess that their cars have become black holes of time and resources. “It’s crazy. A lot of people say there’s no end, and it’s true,” Carton says. “You want more. I’m hooked.” He pauses to reflect. “But at least I’m not spending my money on cocaine.”

An obsession with car-stereo equipment may be a healthier escape than drugs. But fanatics do run the risk of physical repercussions: Dangerous Decibels, a nonprofit research group, classifies all sound over 85 decibels as potentially, well, dangerous. Carton’s system can reach up to 140 — and he plans to boost it to 150 by adding a few more doodads.

“I definitely yell a lot more now,” he concedes. “I’ve been around loud music since I was little.” It doesn’t help that he used to play drums. His dad, who lives in the Richmond area, has been doing bodywork and car-audio installation for 26 years.

Carton observes that a 140-decibel system packs as much aural punch as a gunshot.

“The old-timers tell us to wear earplugs,” notes the Speed Demon sagely.

*****

When it comes to road tripping, I generally listen to Delta blues in the slow lane. But that doesn’t stop me from hopping into Carton’s super-car. Once I’m settled into my leather passenger seat, Oliver closes the door behind me, and I stare at the neon lights whirling around the stereo display. Then I notice a Jägermeister pennant hanging from Carton’s keys.

“Steve,” Oliver calls out as Carton turns the ignition, “you make sure he knows how loud this thing is.”

Carton nods and motors east out of Great Northern’s driveway. The car engine sounds like an airplane, and the purple nitrous oxide tanks — whose contents can increase this car’s oomph by as much as one-sixth of total horsepower for short, periodic bursts — are about 3 feet from my head.

“I’m nervous,” I confess, privately rescinding my newlywed analogy. “The nitrous-oxide tanks look like bombs. And what’s with that Jäger keychain?”

“Dude, don’t worry about what I do on the weekends,” Carton assures me.

I look up at the circular performance tachometer on the dashboard. I’ve seen similar displays before, in video arcades, but this one looks different.

“Why are the numbers so big?” I ask.

Carton pauses for a few seconds. “This may scare you,” he warns. “I have poor eyesight.”

My palms begin to get clammy.

We hang a left onto Shelburne Road, then motor for a hundred feet or so before stopping at a red light. Carton switches the music to Busta Rhymes and revs the engine in neutral. For a few moments, it’s terrifyingly loud. Over the swell of the bass, I can’t even hear myself think, let alone pray.

We are still vibrating at the stoplight when a dumpy, turquoise Honda Civic pulls up next to us. Carton shoots the driver a challenging stare. The guy just raises his eyebrows.

“I FEEL LIKE I’M IN A RACE CAR,” I yell.

“YOU ARE,” Carton reminds me.

I pull on my harness.

The red light changes to green. We rocket forward. But just as I’m about to close my eyes, a police car appears in my side rear-view. Carton sees it, too, and keeps the speedometer under 45. Turning the music down to a pleasant volume, he complains that Burlington cops often target him unjustly.

Then he pulls a U-turn and heads north on Shelburne Road. We’re back at the store in under a minute.

“Hey, what about those nitrous tanks?” I ask as we pull into the driveway.

“Those?” he responds. “They’re empty.”

As I step out of the Acura, my anxiety morphs into indignation. “No nitrous? No ear damage? What is this, Steve?” I say accusingly. “I was prepared for a lot more irresponsibility.”

Oliver and Speed Freak look on incredulously from inside the garage.

Still sitting in the cockpit, Carton explains that the tanks cost $100 a pop. Besides, he’s taking it easy on his car these days.

“So, what, are you going soft on me?” I demand. “Early retirement?”

Carton shrugs defensively. “I wouldn’t say I was retiring. I’d just say I love my car.”

He pauses outside the shop in the sunlight, and the other men join us, lighting up cigarettes.

“I don’t beat it like I used to,” Carton explains. “I’ve built up a respect for my vehicle.” He tilts his head. “But if Corey took you for a ride?”

We all look to Oliver, who declares with a slow, deliberate nod, “If I took you for a ride, you would have to change your pants.”