AN AUDIO DEMONSTRATION OF HOW EARS ARE MORE SENSITIVE TO CHANGES IN LOW FREQUENCY NOISE - FOR INSTANCE GROUND-BORNE NOISE FROM TUBE TRAINS

摘要

The Ground-borne Noise and Vibration Group thought it would be a good idea to remind people of how our ears work and their relative sensitivity to low, mid and high frequency noise. Whilst our ears are less sensitive to low frequency noise than mid and high frequency noise they are more sensitive to change at low frequencies. The paper is an introduction to the Ground-borne Noise session and the audio demonstration will play equal loudness tones at octave bands from 63 Hz to 8kHz and demonstrate what 10dB difference sounds like in each of these octave bands. This will clearly show that the 10dB reduction at 63Hz is subjectively much bigger than at 1kHz. Recordings of tube trains will also be played along with a simulation of what the train would sound like if the building was to be isolated on elastomer bearings or springs. A powerful sound system will be used to provide a very effective demonstration.