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Warning to the readers

New ultrasonic unexplained sounds in Ravne tunnels

TAG: bosnian pyramids, pyramid Bosnia, Visoko civilzation, archaeology, archaeoacustic, voice pyramid, SBRG, SB Research Group

In many of the archaeo-acoustics recordings made in Ravne tunnels by our research group (SBRG) sometimes we could check for absolutely inexplicable sound.

In particular and currently being examined by our sound engineer (H.A. Savolainen) recordings made during the experiment conducted by the physics researcher Slobodan Mizdrak on the top of the Pyramid of the Sun in April 2012.


Fig.1 - The group SBRG at work in the tunnel



During this experiment we placed inside the tunnel two microphones as used by ocean biologists (Hydrophones) for 48 hours continuously.
In this period there were no tourists in the tunnels. The tunnel excavations by the workers of the Foundation of the Bosnian Pyramid of the Sun, or by volunteers had not started either.


At 10pm on 20th April 2012 we recorded this ultrasonic frequency, not present in other phases of the experiment. This was recorded whilst the experiment was carried out on the Pyramid of the Sun / hill Visocica approximately 2.5 km from the tunnels.


Its characteristics are very interesting: it has a higher frequency of 42,000 Hz with a volume of 31dB. If we transpose the audible band 5 octaves down, it seems very similar to the noise of a mechanical mechanism with a constant period.


At that hour no factory in the area were operational and no one was present inside the tunnels with a cell phone switched on. The front door of the tunnel was closed and guarded by a member of our research team.


Fig.2 - Evident a large peak of ultrasound above 42KHz



The microphones for recording ultrasounds were placed at a distance of 15 meters from recorder and inserted into the water. It is not possible that the equipment produced this sound vibration.

Its origin remains unexplained, possibly related to magnetic fields which are occasionally present within the tunnel.

Paolo Debertolis -10 September, 2012
Link to download  audio file in
mp3 or m4a format



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