Researchers in the UK have created a mini model of one of the most famous prehistoric monuments in the world in order to understand its acoustics . They have built a replica of Stonehenge and have carried out a series of tests on it to understand how sounds behaved in the megalith . They have determined that the Neolithic monument had excellent acoustics, and this is helping them to better understand the famous stone circle .

Academics at the University of Salford collaborated with experts from English Heritage on the project. The creation of the ancient megalith was an unusual challenge. It originally consisted of 157 standing stones, in a circle, but today there are only 100. This meant that the researchers had to rely on the insights of archaeologists who helped them to recreate the “pre-historic monument as it would have looked 4,000 years ago, including stones now missing” according to The Guardian . They also used laser scan data obtained from the original site in order to make their work more realistic.

A Miniature Stonehenge

The model created at the University of Salford is 1/12 th the size of the original megalith. To reproduce the stone monument the experts used 3-D printers to make replicas of the stones. After 3-D models were made, silicon molds were made of them. The molds were then used to cast the stones which were made out of a plaster that was mixed with a polymer. To make them authentic imitations they were spray-painted using grey car paint.

The Stonehenge model with the sun position for winter solstice. ( Trevor Cox / University of Salford )

A megalith with a span of 7.5 feet (2.3 meters) was built. This reproduction “has an edge over other replicas of Stonehenge, such as the full-scale one near Maryhill, Washington, for being based on laser scan data” according to The Guardian . Furthermore, many of the stones used on the Maryhill monument are not the right shape, because they are hand-chiseled and are not accurate reproductions.

The Sound Environment of Stonehenge

In order to examine the acoustics of the model the team placed it in the University of Salford’s acoustic chamber and tested it over a seven-day period. They employed a method “used in video game and VR sound creation, one dubbed 'auralisation'” reports the Daily Mail .

To ensure that the acoustics were accurately recorded the researchers had to increase the frequency by a factor of 12, which is in a range that cannot be heard by the human ear. This was to simulate the sonic environment of the original and full-size megalith.

Sound test at 12x the frequency the 1:12 scale model of Stonehenge. ( Trevor Cox / University of Salford )

Then the sounds, usually recordings, were measured as they traveled through the model of the megalith. Some new technology was used to determine how the sounds behaved in the stone monument and also allowed the researchers to hear the sounds .

The Daily Mail quotes Professor Trevor Cox, the project leader, “It is the sound equivalent of visualization. We can virtually place a source of sound in a space ”.

RT results from the Stonehenge model for 12 of the positions measured. The photo also shows the source and receiver used for the ultrasonic testing. ( Trevor Cox / University of Salford )

The researchers now believe that they understand the acoustic environment of the megalith around 2,200 BC. It appears that Stonehenge would not only have been a visual wonder but also a sonic marvel to prehistoric people.

BBC News quoting Cox “considering the henge has no roof and there are lots of spaces between the stones, the acoustics are more like an enclosed room rather than an outdoor space”. The conclusions from the study at the University of Salford were also compared with one that was conducted at the full-scale replica at Maryhill and the results were very similar.

The Mystery of Stonehenge

Stonehenge was built in south-west England over a period of many years. The first henge was possibly constructed some 5000 years ago. Successive groups of people came together to build this remarkable stone megalith . It is believed that they used simple pulley technology to move the massive blocks of granite into place, in what was a remarkable engineering feat.

The role of Stonehenge is a matter of debate. Some believe it was a political or religious site and others that it was a prehistoric astronomical observatory . The extraordinary auditory qualities of the stone circle would have been ideal for mysterious rites and ceremonies. This would seem to support those who argue that the stone circle was used for religious purposes.

Top image: 1:12 scale model to explore how Stonehenge acoustics would have been in 2200 BC. Source: Trevor Cox / University of Salford

By Ed Whelan