MINNEAPOLIS -- Alex Boone was a rookie guard for the San Francisco 49ers in 2009, standing on the visitor's sideline for one of the most raucous moments in the Metrodome's 32-year history. So it means something when the new Minnesota Vikings guard says he thinks the Metrodome's successor is even louder.

"It was way louder here, I thought," said Boone, who made his first of two trips to the Metrodome for the 2009 game that ended with the famous Brett Favre-to-Greg Lewis touchdown pass. "New stadium, people probably turn up. I get it."

Yes, there's a novelty to U.S. Bank Stadium, which opened for football on Sunday afternoon in front of 66,143 fans. But several Vikings players compared its volume favorably to the Metrodome after a preseason game, and initial acoustic readings topped out at 114 decibels during the 23-10 win over the San Diego Chargers. If it's louder for the regular-season home opener on Sept. 18 -- and given the fact the Green Bay Packers are the opponent that day, there's every reason to think it will be -- the Vikings' new home could become the same kind of eardrum-rattling venue their old one was.

"There were some times in there today that it was pretty loud," Vikings defensive end Brian Robison said. "To have that kind of atmosphere in a preseason game, it's kind of a testament to what's going to happen as the season goes on."

Visitors to the Metrodome occasionally insisted the Vikings pumped in crowd noise. No such accusation was levied on Sunday, and it's doubtful one would be in the preseason. But U.S. Bank Stadium has a better sound system than the Metrodome did, and stadium operators showed Sunday how willing they'll be to turn up the volume on everything from music during breaks to the pump-up video that played every 15 minutes during the countdown to kickoff.

"The way the fans are, it's cool that they're so close [to the field]," Minnesota safety Harrison Smith said. "It's going to be very loud, but that's what we love."

The stadium is still in its nascent stage, and it's likely to go through some adjustments before the Packers game. Though players said the new turf felt springier than most surfaces, it still needs to be broken in; players slipped on several occasions on Sunday. Fans experienced long lines and crowded concourses during the soccer match that preceded the first football game here, and though it appeared most fans had gotten to their seats by kickoff, there were some complaints about crowd flow during the game, particularly in the concourses of the upper levels.

But U.S. Bank Stadium has the NFL's closest seats to the field, and the Vikings passed through a field-level club on their way out for pregame warm-ups and after the game. At least on a day where the Vikings won a preseason game, the proximity of fans to the field -- and the noise they can make -- was a popular item with the home players. That even extended to Vikings coach Mike Zimmer's news conference, where fans in the field-level club could see him through a window.

"These people here, walking out to the field through the bar here, it's an experience, but hopefully it was a good fit," Zimmer said.

Then, he motioned to them before joking, "Can they get me a drink? This is going to be rough. We're not going to be able to do this all year."