This from a BBC report:
By Jonathan Amos
BBC News Online science staff, in Salford

People who experience a sense of spirituality in church may be reacting to the extreme bass sound produced by some organ pipes.

Many churches and cathedrals have organ pipes that are so long they emit infrasound which at a frequency lower than 20 Hertz is largely inaudible to the human ear.

But in a controlled experiment in which infrasound was pumped into a concert hall, UK scientists found they could instil strange feelings in the audience at will.

These included an extreme sense of sorrow, coldness, anxiety and even shivers down the spine.

http://news.bbc.co.uk/1/hi/sci/tech/3087674.stm