By Jonathan Amos

BBC News Online science staff, in Salford



The cannon was put at the back of the concert hall

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.

Sound 'gun'

Infrasound has become the subject of intense study in recent years. Researchers have found that some animals, such as elephants, can communicate with low-frequency calls.

Infrasound can be detected at volcanoes and may provide a way to predict eruptions.

INFRASOUND STUDY Lies in the range 10-20 Hz On the cusp of our hearing Can vibrate internal organs Volcanoes emit infrasound Elephants and whales use it

To test the impact on an audience of extreme bass notes from an organ pipe, researchers constructed a seven-metre-long "infrasonic cannon" which they placed at the back of the Purcell Room, a concert hall in South London.

They then invited 750 people to report their feelings after listening to pieces of contemporary music intermittently laced sound from the cannon, played a 17 Hz at levels of 6-8 decibels.

Feel the bass

The results showed that odd sensations in the audience increased by an average of 22% when the extreme bass was present.

"It has been suggested that because some organ pipes in churches and cathedrals produce infrasound this could lead to people having weird experiences which they attribute to God," said Professor Richard Wiseman, a psychologist from University of Hertfordshire.

The pipe put out sound at 17 Hz

"This was an experiment done under controlled conditions and it shows infrasound does have an impact, and that has implications... in a religious context and some of the unusual experiences people may be having in certain churches."

Sarah Angliss, an engineer and composer in charge of the project, added: "Organ players have been adding infrasound to the mix for 500 years so maybe we're not the first generation to be 'addicted to bass'."

Details of the organ infrasound study are being presented to the British Association's annual science festival, which this year is in Salford, Greater Manchester.