Bad noise, like bad news, travels fast. And as far.
The karaoke singing is tolerable, but when the windows rattle and the floor vibrates it makes your blood boil. It must be stopped. So, you run downstairs to the offending apartment and listen at the door, only to discover it is not the correct one. It must have been above you - up you go. Wrong again. Sound travels in mysterious ways, but now out of breath and out of your mind you're at a loss for how to complain.
Can we ever be certain where the noise is coming from?
Yes, but not likely, is the answer according to Tom Ho, chairman of the Hong Kong Institute of Acoustics. It depends on the type of noise. He explained that there were high, medium and low frequencies.
'If you can hear light music or a TV programme in your flat, you can suspect that it is your immediate neighbour,' he said. This is because mid to high frequency sounds, which these are, do not travel far. They are attenuated easily, meaning they tend to get absorbed, (by walls for example) easier than low frequency sound.
'If you are still in doubt as to which flat is causing the sound, source location is possible. But it is complicated and requires an expert to perform the measurement and interpret the result,' Mr Ho explained.