Does sound travel better at night?

My speakers sound better at night ;-) Is there any science behind this?
James 50 and Gregm hit the nail on the head. Yes, less ambient noise allows for more detailed sound from your speakers. When I lived in the sierra mountains, the nights were very quiet and my system came alive with inner detail. Now I live in Santa Barbara and the ambient noises at night are no where as quiet, and subsequently, my critical listening sessions have suffered from it.
Don't forget that your natural cortisone levels tend to be higher in the evening, leading to psychological and physiological chages that impact perception and mood.
no wonder sean and others of the "old guard" have abandoned this site. this topic has been repalyed more times than sex in the city. booooooring!
IT'S THE MAINS. The current cleans up considerably at night when every other power hungry so and so is fast asleep. Try running a power regenerator like PS Audio and you will likely hear the same. Enjoy!