Since the two-week festival started Saturday, drinkers in the 14 giant beer tents have been standing on tables demanding more modern singalong hits such as "Mambo No. 5" and "Living Next Door to Alice."

The manager of the Lowenbrau brewery tent said the restrictions, aimed at curbing violence and raucous behavior, were unacceptable on the weekends.

"The bands were booed, and people asked if the loudspeaker system was broken. ... I was asked when we’d start playing music even though we’d been playing for three hours," said Ludwig Hagn.

The limits were imposed by the Munich city council, which said playing more sedate, folksy music and sticking to a maximum volume of 85 decibels before 6 p.m. would help curb brawls and encourage older visitors who have been put off by the increasingly raucous atmosphere.

"The tents shouldn’t be discos, they should remain Bavarian beer tents," said Oktoberfest manager Gabriele Weisshaeupl. Festival spokeswoman Gabriele Papke said: "It’s a city ruling, and we see no reason to take it back. We’re getting more families in the tents now." The city has appointed an official with sound-measuring equipment to enforce the ruling.

On the opening day, the music was noticeably quieter than in recent years, and the bands had more frequent breaks, during which the party atmosphere subsided.

Hits such as "Hey Baby, Oooh, Aaah" were few and far between, but when they were played, the mood became euphoric, with thousands of inebriated revelers, many in folk-style clothes, leaping onto the long wooden benches.

Jill Henne, a British citizen who lives in Munich, said: "It was dreadful. When you’re in a tent full of people talking, it’s already louder than 85 decibels, so we couldn’t even hear the music. Everyone started standing on the tables and singing the song "Hey Baby," and after a while the band joined in.

"People were getting frustrated and bored. I don’t see how this is going to reduce violence. If people aren’t singing along to the music and dancing, they’re just going to end up drinking more," she said.

Irishman Roger Murphy said the vast quantities of beer helped keep the Oktoberfest alive, regardless of the noise restrictions. "I don’t think people notice after they have had a few beers," he said. The rules and regulations helped make the nonviolent atmosphere possible, he said.

Police said there had been an increase in violence in recent years, with arrests up 15 percent last year to 695. There were 5.9 million visitors last year at the biggest beer festival in the world.

In one incident, a visitor sustained a mild head injury when hit by a flying pork knuckle, a delicacy served in the tents alongside sausages, fried chicken and large pretzels.

Local folk groups have welcomed the restrictions, saying the festival had been losing its traditional Bavarian feel.

David Crossland