Japan is a melody of noise. The signals at pedestrian crossings merrily chirp away whenever the lights flick over; there's a steady, slow, deep ocean wave like "bing, bong" chime rolling across the platforms at main line train stations; and my favourite - two bars of Monsieur Hulot like accordion music every time trains pull into a certain station on Tokyo's Yanamote line.

So different to the unfinished symphony of noise that rolls through Hanoi and Saigon. Constant babble of discordant hoots, whistles, squeals, bells, rumbling exhausts.

Seoul is smooth, like jazz, like something Grover Washington might have written. Oiled and toned, all the notes fit tightly. It all gells. No bumps.

I love all three.