• Profile
• Archaeoacoustics
• Publications

• Introduction
• Avebury
• Stonehenge
• Ring of Brodgar
• Stones of
  Stenness
• Maeshowe
• Dwarfie Stane
• Standing Wave Resonance
• Huntersquoy & Taversoe Tuick
• Stalled Cairns of Orkney
• Easter Aquorthies
• Grey Cairns of Camster

Stonehenge

Stonehenge was constructed in a series of phases over many centuries, and its appearance changed significantly. With each change, its acoustic qualities would also have been transformed. While it is difficult to reconstruct the acoustics from these earlier times, it is possible to study final form of the monument as it stands (dating to between 2500 and 1600 BC). Research here is further complicated because many stones have fallen, or been removed altogether.

Developed in collaboration with acoustician Dr. David Keating, the acoustic tests at Stonehenge were intended to test the most fundamental properties of the monument. A omni-directional loudspeaker was placed at the centre of the large stone circle, and a series of measurements taken along a straight line leading from the centre towards the Heel Stone and Avenue.

Overall, the results suggested that the stones at Stonehenge are able to contain and amplify higher frequency sounds, such as the human voice. In contrast, lower frequency sounds such as drums pass around these sarsens and can be heard for some distance. This means that most sounds made in the centre are not clearly transmitted beyond the rings of stone.

Almost all of the stones at Stonehenge have been artificially shaped. It was noted during the research that the inner surfaces of many stones were dressed to be either flat or concave. This is not visually striking, but could improve the ability of these stones to reflect sound. In contrast, the outward facing surfaces of the same stones are irregular or even convex. The enormous effort invested in dressing sarsens and bluestones into these subtle and barely visible shapes is difficult to explain, but it might suggest that the builders of the monument knew how to emphasise the movement of sound.

Interpreting the acoustics of Stonehenge

It is possible that the contrasting acoustic experiences between the inside and outside of Stonehenge in some ways excluded people from activities at the centre. An audience outside the monument could not have clearly seen or heard events within, perhaps creating a sense of mystery. In contrast, an audience occupying the confined interior of Stonehenge would have heard amplified sounds. It is even possible to generate standing waves, as sound reflects between the enormous stones.