It was the wee small hours and we were the only ones left in our favourite haunt. As the six of us talked, I got up to turn down the volume of the bar's stereo system, which was blasting out music that was coming close to driving us away. Perhaps it was the late hour, the amount drunk, or simply the side-effects of the high-decibel assault, but it took me several trips to realise that each time I turned down the volume, a staff member turned it back up. I suggested to the waiter that, being 3am, there was no good reason to have it so loud. He disagreed: if his bar wasn't 'exciting', why would anyone walking by come in? Our gaze followed his arm motioning to the deserted street, and we remained unconvinced of his logic. But, in his mind, he had won the argument. Renao is the word he used - 'excitement'. The problem is that there is a fine line - and only one character - between renao and caonao (noise). One bar's promotional tactic is another man's eardrum-splitting techno music; the roaring of the dice games and shouting of the players at a busy bar might make for an exciting enticement to join the fray - or inspiration to keep walking. Beijing would not be Beijing without a constant aural barrage: ears are the sensory organ most affected by this city - 'stinky' tofu notwithstanding. The streets are a cacophony of horns, curses, squealing brakes and car alarms; the calls of salesmen, bar touts, arguing couples and shrieking small dogs. Evenings in the hutongs are punctuated by shouts from casual conversation or card games; the soundtrack at most restaurants comes from televisions on full blast. Renao or caonao? It is hard to know. Residents put up with earth-shaking jackhammers at the break of dawn, and the heavy-machinery roars of cranes and construction crews at, literally, all hours of the day and night. But if the sounds of a (ok, my) live band sneak through the (sealed) doors of a bar, the police are called. In the former case, it is the renao of progress; live music to which the neighbours are unable to sing along is caonao. Speakers in shops, bars and restaurants are pointed outwards, ostensibly to boost the renao factor and draw people in. The systems sending out the tunes, without fail, will always be heavy on the reverb - in classic karaoke style - and set to the highest volume level, so that music meant to draw us in is warbled, echo-heavy and distorted. One thing is clear: when it comes to promotional techniques in the 'new Beijing', there is no such thing as caonao. And it is difficult to find a quiet corner where low-volume conversation is possible. Because, after all, what fun is that?