MALE NARRATOR: Some people say it's more comfortable watching a race from home. Die-hard NASCAR fans disagree.
The roar of the engines, the squeal of the tires, then the race to victory lane. It all says, NASCAR. A race car is much more
than steel, gas, rubber and speed. A race car is a science experiment on wheels.
DIANDRA LESLIE-PELECKY: There's nothing like being at the race track. Sure, you can follow all the action from your living
room. But not even the best home theater could capture the full impact of a NASCAR engine firing up. But you can't come to
the track unprepared. You need your scanners, binoculars, sunscreen, and of course, all your favorite driver's
fan gear. But the most important thing you take to the track are your ear plugs.
BRIAN VICKERS: There's really nothing that I can think of in your everyday life that can compare to the sound of a race car.
DIANDRA LESLIE-PELECKY: Sound is a pressure wave. It's made up of alternating regions of dense and
not-so-dense air. When I clap my hands, the air molecules closest to my hands start moving back and forth. They bump
into nearby molecules and start those air molecules moving in the same pattern. When I clap my hands harder, the air
molecules move back and forth much more than when I clap my hands softly. The bigger motion makes the sound louder.
BRANDON THOMAS: It's gotta be triple digits.
JOSH BROWNE: I would say 105 decibels.
JOHN PROBST: Somewhere around a jet engine, I guess.
DIANDRA LESLIE-PELECKY: The decibel scale is logarithmic. Each time the number of decibels increases by ten,
the sound gets ten times more intense. A 60 decibel sound, a normal conversation level, is ten times more intense than a
50 decibel sound, which would correspond to a quiet street. That makes the 105 decibel sound of a race car 32,000
times more intense than that of a normal conversation. Passenger cars use mufflers to decrease the sound intensity.
But mufflers cause problems for race cars.
ANDY RANDOLPH: You consume large quantities of air and fuel, therefore produce large quantities of exhaust, you wanna have as
little of restriction as possible in the exhaust system.
DIANDRA LESLIE-PELECKY: A muffler reflects the sound waves from the engine so they run into each other and cancel
themselves out. Coupled with sound-absorbing material inside the muffler, the result is a quieter car.
ANDY RANDOLPH: A quiet car will not produce as much power as if you were to take the exact same engine and put it
in a car with a lower restriction exhaust.
BRIAN VICKERS: The faster you can take air out of the engine, the faster you can put air in the engine.
And the faster you can put air in the engine, the more power it creates.
DIANDRA LESLIE-PELECKY: Loud is fast. And that's all part of the fun of being at the track.
But loud is also a problem for your ears.
BRIAN VICKERS: Personally, I can't stand to be around a race car without ear plugs in. I mean, some of these guys
have been in the industry for years and years and years. They walk around the garage without ear plugs.
And, well, they can't hear, either.
JOSH BROWNE: I always wear ear plugs at the track. You see a lot of these older guys, they can't
hear anything because they weren't wearing ear protection back in the 1970's or the 80's.
STEVE LETARTE: That's one of the things that you lose the most. I've been racing for twelve or thirteen years.
I always wear my ear protection. But even I have trouble listening to my little girl some days.
DIANDRA LESLIE-PELECKY: Ear plugs decrease how much sound gets into your ears by absorbing and blocking sound
waves. Regardless of whether you use foam or rubber ear plugs, check the NRR, or Noise Reduction Rating. An ear plug with an
NRR of 30 decibels will reduce a 105 decibel sound to 75 decibels. That's roughly the difference between a NASCAR engine,
and someone shouting. When 43 cars go by at full-throttle, even if you're way up in the grandstands, you can
experience a 105 decibel sound. That's like standing three feet from a jackhammer.
BRIAN VICKERS: The reason that NASCAR probably doesn't implement everybody across the board to run mufflers
is because it's really cool to be really loud.
JOHN PROBST: We don't put mufflers on the cars because that's a horrible thing to do to to a race car.
BRANDON THOMAS: Now what fun would that be? People like to hear them. People like to feel them.
STEVE LETARTE: When you're there, you know, sound is one of the great senses of NASCAR. And you wanna hear the
crowd, you also wanna hear the cars. So it's kind of something that always kind of gets you in the heart.
DIANDRA LESLIE-PELECKY: One of my favorite parts of being at the track is feeling the sound of the cars.
Because the pressure waves don't just hit your ears. They hit your whole body. And solids, like bone, actually
conduct sound better than liquids or gasses. So the next time you feel your body vibrate as 43 cars
go zooming past, even with your ear plugs in, that's the sound of science.