Why do sounds seem louder at night?

Answer by Mad Drongo
Submitted on 6/4/2004
Rating:	Rate this answer:
A sound in the environment (the specific noise) becomes more apparent if the margin between its sound pressure level (measured in terms of an Leq for steady noises or say an L10 for varying noises, such as music) and the other noises (the residual noise measured in terms of an L90 and defined as the background noise) gets bigger. In many places the ambient noise levels are driven (sorry) by traffic noise. Thus the background noise level tends to follow the ebb and flow of the traffic. There is generally a peak in noise levels at breakfast time with a plateau phase during the day until another peak is reached at teatime. This is followed by a significant fall in levels until around 01:00 hours then a climb back up to breakfast time levels. The difference between daytime levels and nighttime levels can be 20 dB (plus or minus 20 db). These times and level differences will vary from place to place and will be affected by dominant local sources other than traffic. Consequently a noise that is inaudible during the day can appear quite loud at night due to the reduction in ambient/background noise levels - a bit like a rock being exposed by a falling tide.

FAQS.ORG makes no guarantees as to the accuracy of the posts. Each post is the personal opinion of the poster. These posts are not intended to substitute for medical, tax, legal, investment, accounting, or other professional advice. FAQS.ORG does not endorse any opinion or any product or service mentioned mentioned in these posts.

<< Back to: Acoustics FAQ

[ Home | FAQ-Related Q&As | General Q&As | Answered Questions ]

Question by seandix
Submitted on 10/6/2003
Related FAQ: Acoustics FAQ
Rating:	Rate this question:
Why do sounds seem louder at night?

Answer by hfc
Submitted on 10/30/2003
Rating:	Rate this answer:
i think it might be because there are fewer sounds to mask the source. normally in the daytime there is a lot of vehicular traffic that can mask many sounds. another possibility is that once the sun is not heating the air near the surface of the earth comparitively the air higher up is warmer. this has an effect of a temperature gradient where sound propagation originating from near the earth surface is refracted back down to the earth once it reaches the higher warm air. this allows the sound to travel further with less attenuation.

Answer by khizra
Submitted on 1/24/2004
Rating:	Rate this answer:
sounds travel faster at night because they vibrate so fast

Answer by Jimmy Wong
Submitted on 3/19/2004
Rating:	Rate this answer:
When you are less disturbed by others/surroundings, your mind are more alert and your awareness of sound increases, so you may experience a sensation of 'louder' sound. It is not necessary to be at night, you can have the same feeling of 'louder' sound in the day too.

Answer by Taylor
Submitted on 3/16/2006
Rating: Not yet rated	Rate this answer:
tell me all the answers!

Answer by bobt boy
Submitted on 3/17/2006
Rating: Not yet rated	Rate this answer:
hehehehe

Answer by Jackster
Submitted on 8/11/2006
Rating: Not yet rated	Rate this answer:
Because you're tired and want to go to sleep, and everything is amplified in your mind.

Answer by LOllercakes
Submitted on 8/15/2006
Rating: Not yet rated	Rate this answer:
dude, its cuz u dont want to be caught downloading porn at night.. god

Answer by miles
Submitted on 3/7/2007
Rating: Not yet rated	Rate this answer:
because the sound is comes from vibration we all know that it more silent at night and so some pressure not exist to make the sound louder just observe to your school or market some people not understand what is being told of their companion because many pressure that destruct them and also like to the forest when it is so silent there is an echo because there are no pressure destroy them

Your name or nickname:
If you'd like to create a new account or access your existing account, put in your password here:
Your answer: