It’s 11 p.m. on Saturday night, and O’Sheas is packed. The sounds of live music coming from a stage near the establishment’s Las Vegas Strip entrance permeate the small, frat-party-atmosphere casino. There, adjacent to the Dublin’ Up bar, Hal Savar’s Acoustic Soul plays to a standing-room-only crowd.

The band, Las Vegas’ “original and only live jukebox,” has become the closest thing to a house band O’Sheas has had in its 20 years. At first, the versatile quartet just played in regular rotation on weekends at the casino. Now Acoustic Soul can be found nearly every Thursday, Friday and Saturday at the mid-Strip location.

“The nights we were there, people were crowding into the lounge, and the bartenders were making more money,” Savar says. “The dealers, bartenders and staff started going to their superiors and telling them they wanted our band there.”

The music seems to be agreeing with the audience, which runs the gamut from barely legal to one-foot-in-the-grave. Girls are dancing, guys are chugging, a dude playing blackjack mimes riffs on his guitar-shaped beer container, and everyone is singing along.

Led by 27-year-old Savar on vocals and acoustic guitar, the band features an eclectic mix of seasoned musicians: Nina DiGregorio on violin, bass and vocals; Dave King on keyboards, lead guitar, bass and vocals; and Lanise Hughes, who played in Rick James’ Stone City Band on such iconic recordings as “Super Freak,” on drums. Acoustic Soul’s gimmick is simple but impressive: It plays entirely by request, passing out menus featuring hundreds of songs constituting the band’s repertoire—though the band will play just about anything it can figure out. Audience members request songs by dropping a donation and a Post-It note into the kitty. For certain requests— typically those more technically challenging for the band, particularly violinist DiGregorio—the band requires specific dollar amounts, such as $40 for “Sweet Child O’ Mine” or $100 for “Free Bird.”

“I like the band, but they hustle too much,” says a female bartender who asks to remain anonymous. “They don’t promote the casino or bar.” Even as she tells me this, she is singing along to Acoustic Soul’s take on “Mary Jane’s Last Dance” and staring down a crowd three people deep waiting at the bar, clogging the already-tight passageways between gaming areas.

And while it might seem this kind of entertainment democracy-by-wallet is a bit of a shakedown, Savar assures the added money isn’t the primary reason for the human-jukebox set-up. “It’s the driving force behind the interaction,” he says. “I feel like it gives power to the audience.”

Empowering the fans and providing a more intimate live-music experience is Savar’s objective. When he was putting together the early version of Acoustic Soul, he assessed the state of the cover-band scene in Vegas.

“It seems to me every single cover band I saw in town was similar, a lot playing to tracks, wearing costumes,” Savar says. “I didn’t feel like I connected with any of them.”

Without setlists, flashy outfits or genre restrictions, Acoustic Soul’s goal is to snare a coveted spot as a showroom resident—just as those bedazzled, wig-donning acts have held for years. If the band’s success and reception at O’Sheas is any indication, Acoustic Soul might just stand a chance.

“If I’m blessed and cursed to play in a cover band the rest of my life,” Savar says, “then we’re going to be the best cover band in Vegas.”