When road sings who sleeps

A newly opened stretch of Mumbai's Coastal Road is catching attention for more than just easing traffic.

- JAGRITI DOSI & KAMLESH SINGH

The group of residents said the 'melody' road is “causing significant distress and serves no public necessity.

INTRODUCTION

Drivers cruising along a section of the road are being treated to a musical surprise the surface plays the tune of ‘Jai Ho’ as vehicles pass over it in a steady speed. Mumbai installation uses specially engineered rumble strips. These are grooves cut into the asphalt at a calculated depths and distances to create sound through tyre friction. Officials say the project was executed using Hungarian technology and technical expertise. Hungary has long experimented with melody roads that combine traffic management with creative design. The chosen tune, Jai Ho from Slumdog Millionaire, is audible even with windows closed when drivers maintain the intended speed range.

THE SCIENCE BEHIND

HOW THE ROADS MAKE MUSIC

At first glance, the musical road appears as a series of shallow ridges carved into the asphalt. But each groove is carefully placed using acoustic calculations. When tyres roll over these ridges, they vibrate rapidly, like running a stick along the gaps of a metal fence. The spacing between grooves determines how often the tyre is jolted. Faster impacts create higher-frequency vibrations, while wider spacing produces lower tones. Engineers design these intervals so that when a car moves at a specific speed, the vibrations combine into recognisable musical notes.

Inside the vehicle, the car's body acts as a resonating chamber, amplifying these patterns into sound waves that drivers perceive as a melody. If a driver goes too slowly, the notes stretch and sound offbeat; too fast, and the tune becomes rushed and distorted. The concept builds on traditional rumble strips used worldwide to alert drivers who drift from lanes, but here, the same safety principle is turned into an acoustic instrument.

MUSICAL ROADS AROUND THE WORLD