MP3 listening levels on London underground for music and speech

Abstract

In the last 10years the prevalence of the MP3 players has grown exponentially. The use of devices with in-ear earphones under urban conditions has been reported widely in the press anecdotally. This study compared listening levels for 33 test subjects under quiet conditions and that representative of a London Underground train journey. Calibrated and equalised recordings of underground trains running in tunnels were played through a loudspeaker in an anechoic chamber, whilst pop music, rock music or speech were played through in-ear earphones. Whilst the participates listened to the MP3 player, a Binaural Head and Torso simultaneously measured the noise levels through a second set of identical in-ear earphones. The participants had time to adjust the volume to a comfortable setting on each occasion. Results show very high levels of noise exposure particularly for rock music, 94% of subjects exceeding lower exposure action value within 1h on an underground train journey. The MP3 player volume setting increased significantly more for speech than for music when underground train noise was introduced.