Why California's musical road sounds terrible

Tom ScottAmazing Placesmusical roadLancaster Californiacivil engineeringphysicsacousticsengineering mistakeWilliam Tell Overtureroad tripscience communication

Tom Scott visits the "Musical Road" in Lancaster, California, a stretch of highway with grooves designed to play the William Tell Overture when driven over at 55 mph. He demonstrates that the road is horribly out of tune and proceeds to explain the physics behind how it should work. The video reveals that the problem stems from a simple but critical miscalculation: the engineers failed to account for the width of the grooves themselves in their spacing measurements. In a final ironic twist, Scott explains this is the second version of the road, rebuilt with the exact same mistake after the first was removed due to noise complaints.

Transcription

If you drive down a certain stretch of highway in the California desert, you will hear music. It's supposed to sound a little bit like this. But instead, it sounds like this. That was the musical road of Lancaster, California. And as you may have heard, it's a little bit out of tune. A lot of money was spent on that road. It was a publicity stunt for a car company who wanted to show off how clever they are. And doing the calculations for something like that isn't really difficult. A musical note is a vibration in the air at a particular frequency. And those vibrations can be made by a violin string or synthesized by a computer, or in this case, made by vehicle tires hitting grooves in the road. The closer the grooves are, the faster the vibrations, and the higher the note. So take the speed limit, divide by the frequency of the note you want, and that's how often there should be a groove in the road. And if people travel at the wrong speed, well, it shouldn't really matter. It'll just be like slowing down or speeding up any other bit of music. It'll be in the wrong key, but it'll still sound right to most people's ears. It won't sound like that mess. So, uh, what went wrong? At this point, I am indebted to David Simmons-Duffin, an assistant professor of physics at Caltech, whose interests include quantum field theories and playing baroque violin, because he was, as far as I can tell, the very first person to figure out what went wrong. And the problem was probably the English language. Whoever did the calculations said that the grooves should be so far apart, let's say four inches for the first note. And they meant that there should be a groove every four inches. But whoever gave the instructions to the work crew said that the grooves should be four inches apart. And that was interpreted as four inches between the end of one groove and the start of the next one. They didn't include the width of the groove itself. But your ears definitely do include it. The highest note on that section of the William Tell Overture should be one octave higher than the lowest. That means the frequency should be doubled and the grooves should be half the distance apart, and they are, if you don't include the width of the groove itself. That error means that every note is distorted, not by a fraction of its value, like if you're traveling at the wrong speed, but by a constant amount, by the width of the grooves. The higher the note, the greater the effect of that distortion. And the result is the mess that you are about to hear for a second time. And the really strange part, this is the second musical road built in Lancaster, California. The first one, built by the car company, was too close to residents who complained about the constant noise and probably this note here. So the city paved over it and rebuilt it to the exact same wrong blueprints. That's a take. That is a take right there. And in order to celebrate that take, I'm going to put my foot down. This is an SUV. It doesn't, it doesn't do that.

Visual Timeline

0:00
medium shot eye-level Informative and intriguing.

A man is driving a car and speaking directly to a camera mounted on the passenger side.

"If you drive down a certain stretch of highway in the California desert, you will hear music."

Setting: Inside a moving car on a highway — Bright, natural daylight from the front and side.

People (1):

• sitting in driver's seat, driving, wearing maroon t-shirt and jeans (implied), short, light brown/blond hair — speaking, neutral expression

steering wheel (black)dashboard (black)
Colors:gray, maroon, beige, black, pale blue
0:04
medium shot eye-level Explanatory.

The man continues speaking and driving, gesturing with his right hand.

"It's supposed to sound a little bit like this."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — speaking, looking at camera

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
0:08
close-up low angle, mounted near the front wheel Upbeat, triumphant (matching the music).

A montage of shots showing the car driving on the highway, set to the intended music.

Setting: Desert highway in California — Harsh, bright daylight.

car wheel (silver)road lines (yellow)

Text: "William Tell Overture Rossini"

Colors:gray, silver, yellow, light green, pale blue
0:13
wide shot (POV from driver's seat) eye-level, from inside the car Anticipatory, setting up a contrast.

The man finishes his sentence and the car begins to drive over a section of road with visible grooves.

"But instead, it sounds like this."

Setting: The Musical Road, Lancaster, California — Bright, direct sunlight.

car hood (black)trees (light green)
Colors:beige, gray, pale blue, light green, black
0:20
wide shot (POV) eye-level, from inside the car Dissonant, slightly comical, and jarring.

The car drives over the grooved road, producing a discordant, out-of-tune melody.

Setting: The Musical Road, Lancaster, California — Bright daylight.

grooved pavement (gray)
Colors:gray, beige, pale blue, light green, dark gray
0:31
medium shot eye-level Amused, slightly critical.

The man drives and speaks, pointing over his shoulder with his thumb.

"That was the musical road of Lancaster, California."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — speaking with a slight smirk

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
0:40
medium shot eye-level Explanatory, slightly cynical.

The man continues driving and explaining the origin of the road.

"A lot of money was spent on that road. It was a publicity stunt for a car company who wanted to show off how clever they are."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — serious, speaking

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
0:48
medium shot eye-level Educational.

The man turns off the main road and begins to explain the physics of sound.

"A musical note is a vibration in the air at a particular frequency."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — focused, speaking

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
0:58
medium shot eye-level Informative, engaging.

The man explains how the musical road creates sound, gesturing with his hands.

"or in this case, made by vehicle tires hitting grooves in the road."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — expressive, speaking

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
1:45
medium shot eye-level Scientific, clear.

The man explains the calculation for the groove spacing.

"So take the speed limit, divide by the frequency of the note you want, and that's how often there should be a groove in the road."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — speaking clearly

steering wheel (black)

Text: "55mph", "24.6m/s / 440Hz = 0.056m = 5.6cm"

Colors:gray, maroon, beige, black, pale blue
1:53
medium shot eye-level Analytical.

The man explains that driving at the wrong speed would change the key, but not cause the dissonance heard.

"well, it shouldn't really matter. It'll just be like slowing down or speeding up any other bit of music."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — thoughtful, speaking

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
2:05
medium shot eye-level Inquisitive, leading.

The man poses the central question of the video, looking directly at the camera.

"So, uh, what went wrong?"

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — questioning expression, eyebrows raised slightly

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
2:10
medium shot eye-level Academic, respectful.

The man credits the physicist who solved the mystery, gesturing with his hands as if presenting information.

"to David Simmons-Duffin, an assistant professor of physics at Caltech, whose interests include quantum field theories and playing baroque violin,"

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — speaking, looking slightly off-camera

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
2:22
medium shot eye-level Revelatory, slightly ironic.

The man reveals the surprising root cause of the error.

"And the problem was probably the English language."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — serious, making a point

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
2:32
medium shot eye-level Explanatory, detailing the mistake.

The man explains the specific linguistic misunderstanding between the engineers and the construction crew.

"And they meant that there should be a groove every four inches. But whoever gave the instructions to the work crew said that the grooves should be four inches apart."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — speaking emphatically

steering wheel (black)
Colors:gray, maroon, beige, black, pale blue
2:40
medium shot eye-level Precise, analytical.

The man clarifies the error: the space between grooves was measured, not the distance from center-to-center.

"And that was interpreted as four inches between the end of one groove and the start of the next one. They didn't include the width of the groove itself."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — serious, explaining

Colors:gray, maroon, beige, black, pale blue
2:50
close-up overhead Visually explanatory.

A split-screen graphic illustrates the correct vs. incorrect measurement of the grooves.

"That means the frequency should be doubled and the grooves should be half the distance apart, and they are, if you don't include the width of the groove itself."

Setting: N/A - graphic overlay — N/A - graphic overlay

road grooves (gray)

Text: "Red dotted lines and white measurement bars illustrating the spacing."

Colors:dark gray, light gray, white, red
3:00
medium shot eye-level Conclusive, summarizing the physics.

The man explains the consequence of the error: a constant distortion, not a proportional one.

"That error means that every note is distorted, not by a fraction of its value, like if you're traveling at the wrong speed, but by a constant amount, by the width of the grooves."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — speaking, looking at camera

Colors:gray, maroon, beige, black, pale blue
3:10
medium shot eye-level Ironic, incredulous.

The man delivers the final ironic twist of the story.

"And the really strange part, this is the second musical road built in Lancaster, California."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — slight smile of disbelief

Colors:gray, maroon, beige, black, pale blue
3:22
medium shot eye-level Amused, concluding.

The man concludes the story with the punchline that the mistake was repeated.

"So the city paved over it and rebuilt it to the exact same wrong blueprints."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — smiling, shaking his head slightly

Colors:gray, maroon, beige, black, pale blue
3:27
medium shot eye-level Upbeat, concluding.

The man smiles at the camera as the outro graphic appears.

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — smiling

steering wheel (black)

Text: "AMAZING PLACES", "tomscott.com @tomscott /tomscott tomscottgo"

Colors:gray, maroon, black, white, pink
3:35
medium shot eye-level Playful, celebratory.

In an outtake, the man decides to accelerate the car.

"And in order to celebrate that take, I'm going to put my foot down."

Setting: Inside a moving car — Bright daylight.

People (1):

• sitting, driving, wearing maroon t-shirt, short, light brown/blond hair — smiling, looking to the side

steering wheel (black)

Text: "AMAZING PLACES", "tomscott.com @tomscott /tomscott tomscottgo"

Colors:gray, maroon, black, white, pink