The European-style roof atop StubHub Center, made of a fabric designed to contain and reverberate crowd noise, was not in the original design plans for the $150-million stadium in Carson.

It was added at the last minute, at a cost of $8 million, by stadium developer and operator AEG on Jurgen Klinsmann’s insistence after the former German soccer star and U.S. national-team coach toured the facility before it opened in 2003.

Who knew that 14 years later the tensioned membrane structure, manufactured by Birdair, Inc., would be one of the keys to transforming the 27,000-seat soccer stadium into an NFL-worthy home for the Chargers, who will host the Seattle Seahawks in their first StubHub exhibition game Sunday night?

“Home-field advantage is so important in the NFL, so we’re very excited to see whether that structural element can add any benefit to the crowd noise,” said A.G. Spanos, president of business operations for the team. “Obviously, it’s a small stadium. It seats 27,000. Our goal is to make it sound like 90,000.”


If the Chargers rebound from a 5-11 season and challenge for a playoff spot, and if their offense is high-powered and entertaining, their temporary home for three seasons could, at times, sound something like an NFL stadium. It will never look or feel like one, but that isn’t necessarily a bad thing.

StubHub’s football seating capacity will be less than half of every other NFL stadium. Not not since 1965, when the Oakland Raiders played their final season in 22,000-seat Frank Youell Field, has an NFL or AFL team played in a facility this small.

“I think it presents a great opportunity for us to give our fans a very unique experience,” Spanos said. “Every seat is going be close to the action by virtue of the size of the venue.”

The elevation of the seats in the last row of StubHub Center is lower than the first row of luxury-suite seats in most NFL stadiums. The Chargers will add three rows of field-level bleachers in at least two corners of the end zone, bringing hundreds of fans who can afford the high-priced seats even closer to the action.


A moderate sized crowd looks on from the shaded seats on the West side of StubHub Center as Chargers and Rams practice together. (Robert Gauthier / Los Angeles Times)

The proximity of virtually every section to the field will provide a level of intimacy few NFL stadiums can match. Most fans will be able to hear quarterback snap counts and audibles. Coaches screaming on the sidelines and bone-crushing collisions on the field will be within earshot.

“Everybody is so close to the field that every visual sense will be heightened,” said Michael Roth, vice president of communications for AEG. “You’ll smell some of the sweat, you’ll touch the players when they come over the sides, you’ll hear them … it’s football for the senses.”

Several players raved about their new home after last Saturday’s joint practice with the Rams, which attracted about 8,000 fans to StubHub. They could only imagine how the place will feel and sound when it’s packed.


“The atmosphere was amazing,” defensive end Melvin Ingram said. “It feels like everybody is so close. … The fans are even more stoked than we are. When you come out here and see them so hyped, I have no choice but to lay it on the line for them.”

The Chargers, in conjunction with stadium and league officials, have worked furiously for months to upgrade and adjust the facility to accommodate the larger crowds expected for football, from adding seats, parking, concession stands and restrooms to a massive expansion of the press box.

The bleachers in the second deck on the east side of the stadium were replaced by tip-up seats and moved to the berm on the north side, adding 1,000 seats. A new section of upper-level bleachers, which will seat 330, was erected in the southeast corner of the stadium.

Fans watch from the South side of the stadium as the Chargers and Rams conduct a joint practice. (Robert Gauthier / Los Angeles Times)


The 43 luxury suites have been renovated with new seats, furniture, community tables, and engineered hardwood floors instead of dated carpet.

Fans will have use of the restrooms and concession stands at the 8,000-seat tennis stadium next door. A new concession area with food trucks, beer trucks and high-end portable restrooms will be added behind the berm on the north side.

“These are not construction-site portable restrooms,” Roth said. “They’re movie-studio-set ones.”

Katie Pandolfo, the facility’s general manager for 13 years, said most NFL stadiums have a ratio of 120 fans to one concession-stand point of sale.


“We tried to get even lower than that,” Pandolfo said. “We’re at 112 to one.”

Parking lots will open for tailgating four hours before the game, but tailgating will not be allowed on the lots located on Cal State Dominguez Hills property.

Fans wishing to use public transportation can take free Chargers Express shuttles from the Harbor Gateway Transit Center on the Silver Line and the Del Amo station on the Blue Line. Drop-off will be in front of the stadium.


An official pregame tailgate will begin three hours before games on the plaza concourse on the south side of the stadium, which can accommodate up to 8,000 people.

There will be at least 16 food trucks, featuring a variety of Los Angeles-area vendors, several large-screen televisions for the viewing of early games, an outdoor bar, shade areas and stages for pregame radio and television shows.

The Chargers will have full use of the American Express Stadium club, which seats about 250 on the south side, the 14 cabanas, which seat four to six people, outside the club and the Jim Beam Champions Lounge, from where fans can see players coming in and out of the locker rooms.

The press box is undergoing a major facelift. A third row was added to the main box, boosting capacity from about 35 to 53. Floors were constructed on the roof of the luxury suites so an auxiliary press box could be built on both sides of the main box.


In all, the new configuration will accommodate more than 200 media members. Though the auxiliary box will be outdoors, the working area will be protected by the stadium roof.

Two new radio booths were built outside the south side of the press box, and a large new booth on the north side will serve as a security command post for police and NFL officials.

Two booths were added on each side of the press box for the NFL-mandated 20-yard-line television cameras, and a stairway allowing access to the roof of the main box was built to accommodate the 50-yard-line camera.

Two of the eight booths on the first floor of the press box were reconfigured with riser systems to accommodate coaching staffs. The other six booths will house the national television crew, radio crews for both teams, instant-replay officials, game-clock managers and medical spotters.


“We had the network and NFL officials fly in, we brought in a lot of experts to look at all the infrastructure that needed to be put in place so the replay system can work, so the coach-to-quarterback communication can work,” Spanos said. “All those behind-the-scene things needed to be done.”

Chargers players enter the field to participate in a joint practice with the Rams at StubHub Center. (Robert Gauthier / Los Angeles Times)

To accommodate 53-man NFL rosters, four small locker rooms were converted to two larger ones with 60 cubicles in each. Both teams will have access to training rooms and a weight room. There will be small postgame news conference rooms for each team and rooms for game officials and the chain gang.

The Chargers will have the use of the new 52 X 20-foot video board on the south side of the stadium. A ribbon board was added to display detailed game information, out-of-town scores and fantasy league stats.


The Chargers are paying for the bulk of the renovations and upgrades, which Spanos estimated to be in the “tens-of-millions-of-dollars” range.

Eric Smith, former stadium voice of the Dodgers, has been hired as StubHub’s public-address announcer, and Mark Tamar, who spent the past decade with the Seattle Seahawks, has been hired as vice president of fan experience.

Tamar, a UCLA graduate who previously worked for the Lakers and Dodgers, was instrumental in creating the “12th-Man” experience in CenturyLink Field. In addition to spearheading game-day entertainment, he will look to “raise the roof” in StubHub Center.

“Seattle has a similar canopy above its stadium, and it’s as loud as any stadium I’ve been in,” Spanos said. “We hired Mark Tamar with two objectives: to create a great fan experience and to create a great home-field advantage.


“Seahawk fans take a lot of pride in knowing they can impact the outcome of the game. I think the fans underestimate the role they can play. We need to make StubHub a fierce place to play.”

mike.digiovanna@latimes.com

@MikeDiGiovanna


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