Stadium Spotlight: What makes Oregon's Autzen Stadium so loud?

Think of a potato chip. Not so much a ridged Ruffles or a crushed-up Lay’s, but more a Pringle. That shape -- the curvature of the chip -- matches Oregon’s Autzen Stadium. The Eugene, Ore., venue has that same potato chip shape for the seating bowl, with sidelines sweeping taller than the low-strung end zones.

Opened in 1967, Autzen’s frugality of design -- the entire structure was originally built for $2.5 million -- has led to its character, even during a renovation in 2002 that boosted capacity by 12,000 to 54,000 seats. Standing-room-only tickets bump actual game-day capacity to roughly 59,000.

While countless stadiums make claims to the crown of loudest in college football, Autzen routinely ranks atop the list. You can call it frugality of design, which wasted little space and pushed fans close to the field, but Christopher Mitchell of AECOM, one of the architects on the Autzen remodel, tells SI.com the simplicity of the potato chip-style bowl really lends to a roaring ambiance.

“It is like a double-sided amphitheater,” he says. “All the energy is concentrated.”

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With just one deck that flows freely, the seats and noise created from the wild Ducks fans doesn’t get broken up by structure and rings of glassed-in luxury seating. Add in a suite building on the north side with a flat, solid surface and a roof on the south side both bouncing sound back toward the field, and “all those things help concentrate sound back in toward the bowl,” Mitchell says.

During original construction, Oregon took unused space north of the Willamette River connected to campus by a footbridge and, as Mitchell describes it, scraped up the earth around it to pour concrete on, forming the backbone of the seating bowl. With the 90-acre site full of bedrock, the locally sourced infill builds up around Autzen, encasing the state’s largest sports venue in earth and sinking the field, which also adds a noise-retaining benefit.

“What we liked was the purity of the form of the bowl,” Mitchell says. “It is quite striking and beautiful.”

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The 2002 expansion forced designers to slice off the south side of the seating bowl and rebuild it with the same geometry as the original, simply making it taller in the process of adding 12,000 seats and 32 high-rising luxury suites. On the backside, they reworked the land to carve out a new concourse to tie into the rest of the stadium, adding in new concessions and amenities.

“The geometry is still very similar,” Mitchell says. “It is a little lopsided, but all the lines kind of flow.” Even with the remodel, the outline of Autzen mimics the shape of Oregon’s “O” logo, designed by Nike to resemble Autzen on the outside and Hayward Field, Oregon’s legendary track venue, on the inside of the O.

The original 1967 aesthetic featured a glulam wood roof covering about 2,400 of the 42,000 seats. The redesign embraced the original roof overhang, making it larger and recycling the original pieces in a new Autzen Stadium entryway design. The potato-chip shape remained, and with it, the signature boom of the Autzen crowd.

Tim Newcomb covers stadiums, design and gear for Sports Illustrated. Follow him on Twitter at @tdnewcomb.

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