Mike Zimmer makes a weekly plea to fans with a message that — not coincidentally — usually ends up displayed on the massive videoboard inside U.S. Bank Stadium the first time his defense takes the field.

Zimmer begs for noise, loud enough to keep ears ringing hours later. His motive is simple: The Vikings defense ranks among the NFL’s best under any circumstance. At home, they own the league’s stingiest defense.

The combination of Zimmer’s defense and a raucous home atmosphere that surprisingly mirrors the Metrodome in decibel level should make the Vikings a tough out in the playoffs.

That’s why players can’t exhale after securing the NFC North title and at least one home playoff game with Sunday’s 34-7 thrashing of the Cincinnati Bengals.

With two games remaining, the Vikings have a shot to earn home-field advantage throughout the playoffs. That carries added significance with the NFC race being more wide open than Montana prairie.

The NFC won’t feature a prohibitive favorite when the playoffs start. Five teams already have double-digit win totals, so no postseason result will feel like an out-of-the-blue upset. Seeding matters only as it relates to location of games.

“[Having home playoff games] is a big deal,” Zimmer said, “but I don’t know it’s like everything.”

That’s true. The Vikings are good enough to win anywhere largely because of their defense. Being at home improves their chances because their defense shows extra bite.

The Vikings allow a league-low 12.9 points per game at home this season. They also rank first in third-down defense at home (25.3 percent), though they are historically stout in that category, home or road.

Their third-down defense overall (26.1 percent) represents the lowest mark in the NFL since the 1991 New Orleans Saints posted that exact figure.

The Bengals looked helpless on third down, converting only one of 13 chances as the Vikings corkscrewed them into a heaping mess.

“That’s a great feeling,” nose tackle Linval Joseph said.

Not for the offense, which already faces a challenging chess match against Zimmer’s exotic scheme. Deafening noise complicates matters because it interferes with communication at the line.

Opponents have committed 11 pre-snap penalties at U.S. Bank Stadium this season, including eight false starts.

“It’s very difficult because physically we’re getting after them,” defensive end Brian Robison said. “And then mentally it’s rough on those quarterbacks because they’re trying to make checks, trying to make calls and get the right protection against our defense that we’re showing.”

For all its warts, the Metrodome provided an undeniable advantage with its noisy atmosphere. Vikings officials initially were curious about how crowd noise inside U.S. Bank Stadium would compare to the Dome because the new stadium is far more spacious. If anything, it’s been on par, or slightly louder.

Decibel levels reached 119.8 for the Los Angeles Rams game Nov. 19. That’s roughly the same decibel reading measured in the Dome for the Vikings playoff game against the Dallas Cowboys in the 2009 season.

Robison has played in both stadiums and gives his new home a slight edge in noise.

“It’s unbelievable how loud that stadium gets,” he said. “When you’re on the sidelines, sometimes it doesn’t sound as loud. But when you get out on the field — I don’t know if it’s the way those tiles are aiming or what — but when you go out on the field, you can actually hear the decibels go up. It’s crazy.”

Intense noise not only creates communication issues but it also slows reaction time at the snap. Imagine giving Everson Griffen and Danielle Hunter a split-second head start with their pass rush.

“It is definitely to our advantage,” cornerback Terence Newman said. “They can’t communicate. Half the time we can’t communicate.”

Several defenders echoed that statement, saying they have trouble hearing their own play calls because of the noise. Not that they’re complaining. They also know their defense can dominate regardless of venue.

“Put us anywhere and we’ll have fun,” linebacker Anthony Barr said.

They seem to find an extra gear at home though, and any edge becomes paramount in the playoffs, especially with an NFC bracket that looks wide open.


Chip Scoggins chip.scoggins@startribune.com