Sounds produced inside circle would have been less audible to anybody outside, research finds
Scientists have succeeded in accurately recreating the monument’s original soundscape. The new research – carried out by acoustics engineers from the University of Salford in Greater Manchester – has revealed that the 20-40 tonne stones acted as a giant amplifier, which increased the decibel count of various sounds potentially produced in the monument’s inner sanctum by between 10 and 20 per cent (up to 10 decibels), compared to a more open environment. However, the research also demonstrated that any sounds produced inside the temple would have been much less audible to anybody outside the circle, despite the monument almost certainly not having a roof. The findings therefore suggest that any sounds generated by activities carried out inside the circle were not intended to be shared with the wider community. This reinforces theories suggesting that the potential religious activities conducted inside Stonehenge were reserved for an elite of practitioners, rather than for a wider communal congregation.
Cox, T. J., Fazenda, B. M. and Greaney, S. E., Using Scale Modelling to Assess the Prehistoric Acoustics of Stonehenge, Journal of Archaeological Science, vol. 122, p. 105218, from http://dx.doi.org/10.1016/j.jas.2020.105218, October 2020. DOI: 10.1016/j.jas.2020.105218
With social rituals usually involving sound, an archaeological understanding of a site requires the acoustics to be assessed. This paper demonstrates how this can be done with acoustic scale models. Scale modelling is an established method in architectural acoustics, but it has not previously been applied to prehistoric monuments. The Stonehenge model described here allows the acoustics in the Late Neolithic and early Bronze Age to be quantified and the effects on musical sounds and speech to be inferred. It was found that the stone reflections create an average mid-frequency reverberation time of (0.64 ± 0.03) seconds and an amplification of (4.3 ± 0.9) dB for speech. The model has a more accurate representation of the prehistoric geometry, giving a reverberation time that is significantly greater than that measured in the current ruin and a full-size concrete replica at Maryhill, USA. The amplification could have aided speech communication and the reverberation improved musical sounds. How Stonehenge was used is much debated, but these results show that sounds were improved within the circle compared to outside. Stonehenge had different configurations, especially in terms of the positions of the bluestones. However, this made inaudible changes to the acoustics, suggesting sound is unlikely to be the underlying motivation for the various arrangements.
Keywords: Acoustics, Stonehenge, Prehistoric, Scale modelling, Archaeoacoustics
