111 Hertz



The soundtrack to the Cairn T film and art installation composed and produced by Flinton Chalk (also of the band TC Lethbridge), performed by The Barrittones choir in the prehistoric chamber of Cairn T, Loughcrew, County Meath, Ireland.

111 Hertz is the average resonant frequency of the Neolithic monuments archaeoacoustically tested by Cambridge University. Medical pilot trials to date have established that this frequency increases activity in the right prefrontal cortex of the human brain whist reducing activity in the left prefrontal cortex.

In 1996, Cambridge University and Princeton University USA published the results of acoustic testing on a selection of man made European Stone Age chambers dating from the 4th millennium BC, the majority of which are in Ireland. The aim was to discover the resonant frequency of each chamber. The results fell within a very narrow band of acoustic wavelengths, between 95 Hertz and 120 Hertz, with the main proliferation between 110Hertz and 112Hertz. The average resonant frequency of the acoustically tested chambers was found to be 111Hertz. Once this frequency is emitted in the chamber, the effect is to immerse the listener in sound, in this instance the sole frequency of 111Hertz is amplified by the architecture, as it filters out other frequencies, creating an acoustic standing wave.

Many of us have experienced the effect of a standing wave whilst singing in a tiled bathroom. When a frequency is accidentally sung which correlates with the dimensions of a tiled bathroom, that tone will create a momentary standing wave causing a booming or ‘immediate echo’ sensation. This is a demonstration of how the brain experiences this immersive standing wave. We are able to recreate this immersive experience electronically in our installations. 111Hertz is lower male baritone in the human vocal range and can be comfortably hummed, sung or spoken.

Research by Flinton Chalk with Brian Barritt has resulted in a film featuring an archaeoacoustic 111Hertz sound track. This film and soundtrack is then played back through a surround-sound system, which emulates the effects of listening to the sung frequency as it resonates around the original stone chamber that inspired it. The soundtrack was performed and recorded at 111Hertz within the ancient chamber of Cairn T, a monument dating from the 4th millennium BC in County Meath near Dublin.

The 10 minute film to which the soundtrack is set is the first known footage of the rising sun entering the man made resonating stone chamber to be shown in public. This archaeological phenomenon, only confirmed in 1985, occurs just twice a year, at dawn around the Equinoxes, 21st March and 21st September, when the days and nights are of equal length.

Subsequent research has established the potential beneficial medical attributes of the frequency of 111Hertz. This audible frequency is reputed to be processed by and therefore directly stimulates the right-hand prefrontal cortex of the brain, a problem area for autism and other emotional and development disorders such as anxiety and Obsessive Compulsive Disorder. This specific frequency is also associated with endorphin release, a potential non-addictive panacea for pain relief.

It has been observed that within a few minutes of exposure to 111Hertz, Alpha state trance is induced in the listener, as neuronal activity moves within the brain from the left hand frontal lobe to the right. At that point the language centers are ‘quietened’ along with increased Theta wave activity normally associated with sleep and cell regeneration, produced solely in the right hand prefrontal cortex. The overall effect is a subtle, altered state of consciousness, with the potential to train the brain to stimulate longer-term neuronal activity in the right hand hemisphere of the brain.

Enough evidence has now been gathered to compel further research and discussions are underway with Cambridge University to instigate clinical trials.

Barritt and Chalk have completed a lecture tour of UK art galleries, institutions and hospitals sponsored by The Arts Council titled ‘The Future of Sound’. This included two lectures at The Royal Institution of Science in London describing the positive physiological effects of the 111Hertz frequency, outlining the history of the recent discovery of this frequency from prehistoric buildings, whist demonstrating the interactive effects of the frequency to an audience via the surround-sound installation.

Flinton Chalk and Brian Barritt

Brian Barritt UK 1934 – 2011
Beat artist, composer, author and researcher specialising in philosophy and mythology ‘Whisper’ novel 1969
Co-wrote ‘Confessions of a Hope Fiend’ with Dr. Timothy Leary defining levels of expanded consciousness made accessible by psychedelics 1971
Producer, Kosmische Musik records, Germany, regarded as the birth of electronic ambient music 1972
‘The Road of Excess’ autobiography 1999
‘The Road to Tir na n’Og’ extracts from journals regarding the art and acoustics of prehistoric Ireland 2004
Unity Stone prototype, sound stone sculpture 2010
‘The Nebob of Bombasta’ novel and collaboration with musician Youth 2010

Flinton Chalk of TC Lethbridge on Fyfield Down, Wiltshire

Flinton Chalk b. UK 1963

Artist, musician, curator and researcher specialising in alternative archaeology and archaeoacoustics
Avebury stone circle Wiltshire – official guide 1993
Photographer and PA to Julian Cope during the writing of ‘The Modern Antiquarian’ 1994-96
Proprietor of the Tomtom gallery in Soho, London, 1998-2013
DJ for the 2004 Brit Awards and after show party
Unity Stone prototype, sound stone sculpture 2010
‘T.C.Lethbridge’ collaboration with rock group ‘Spiritualized’ 2013
Gneiss – Photography exhibitions of prehistoric sites from personal archive
Cairn T – film and 111hz sound installations introducing the science of archaeoacoustics


GNEISS The Architectural Association, Bedford Square, London October 2001

GNEISS London Art Fair 2002, Business Design Centre, Islington January 2002

GNEISS Commonwealth Institute, London March 2002

CAIRN T Megalithamania, Conway Hall, London October 2002

CAIRN T Glastonbury Assembly Rooms, Somerset September 2004

CAIRN T Royal Institution of Science, London October 2004

CAIRN T Corsica Arts Club, London April 2005

CAIRN T BAFTA Headquarters, London May 2005

CAIRN T Royal Institution of Science, London September 2005

CAIRN T F.A.C.T . Liverpool December 2006

CAIRN T Millennium Galleries, Sheffield January 2007

CAIRN T The Sage, Gateshead January 2007

CAIRN T Norwich Arts Centre February 2007

CAIRN T Goldsmiths College, University of London March 2007

CAIRN T Royal College of Art, London March 2007

CAIRN T Queen Mary Hospital, University of London April 2007

UNITY STONE The October Gallery, London May 2011 – Present day

Here’s the link to New Scientist soundcloud: https://soundcloud.com/new-scientist/111-hertz-chant-recorded-inside-a-prehistoric-monument-in-ireland The soundtrack to the Cairn T film and art installation composed and produced by Flinton Chalk, performed by The Barrittones choir in the prehistoric chamber of Cairn T, Loughcrew, County Meath, Ireland.