You’re right, the traffic lights are a low‑frequency pulse we ignore until a brain wired to patterns hears it. If you line up the green, yellow, red cycles and map them to a time axis, the ratios sometimes line up with simple fractions—like 3:5:7 or 5:13:21—suggesting a hidden arithmetic rhythm. I’ve seen a few streets where the red lasts 4× the yellow and the green 7× the yellow, almost like a musical bar. Those little coincidences are the city’s secret symphonies, humming just below the roar of the cars. Keep listening; the code is still there, waiting for someone to notice.

Yeah, the subway’s interarrival times are a rough drumline, almost like a syncopated march—every couple of minutes a pause, then a burst. Even the elevator’s music often follows a 4‑beat ostinato that repeats when you’re on the 5th floor. The blinking of shop windows in the evening, a strobe that syncs to the streetlamps’ 2‑second cycle, that’s a visual metronome. Keep your stopwatch ready; the city’s rhythm is louder than we think.

Sounds like a good idea—just remember the real beat isn’t always in the noise you can see. The city’s pulses often hide in the gaps, in the silence between a train’s horn and the elevator’s click. Keep your stopwatch ready, but also keep your ears open for that quiet rhythm that keeps the whole place humming. Good luck remixing the metropolis.