By Tom Danley • March 10, 2017 The Great Pyramid of Giza. Let Me Take You Higher After filming at that level and climbing up through a tunnel, we got to the next level up to do the same filming bit. It was in this room that we found a huge pile of burlap sacks filled with the chips the diggers had removed from the level below. This room also featured a large trash pile and hundreds of water bottles from the diggers. It’s clear they were at work for some time. Our passage to the rest of the upper levels was a real pain. Whoever did this part of the work used explosives. Essentially, this turns the experience into rock climbing. I got as far as I was able to go without help. Fortunately, the camera and lighting guys were climbers and helped me up the last step. The top level has a peaked ceiling. There I had some time to look into any and all cracks I could find with my headlamp. I found a place which looked like it opened up into a room as I could not see anything past the edge I was peering in. On the next trip up, the camera guy put a 40 ft (12.1 m) fiberoptic bundle into the crack to see what it was. It turned out to be a very long (couldn’t see the end) row of blocks all aligned (instead of the normal stager pattern) together — all with big parts of the lower corner broken off. While the accelerometer footage was good for the movie, the measurements were not informative. The signal was totally swamped by 50 Hz and other electrical noise. I had a DAT recorder on hand, recording the test and mic signal for later analysis. After being home for a few months and trying to see what else might be revealed on the DAT tape using Hyperception software, I found several things I couldn’t have seen with the TEF. The TEF showed a large number of room modes some going below 20 Hz. How Loud Does It Get? While doing an FFT on the between-sweep time or quiet parts of the recording I found some very LF sound — resonances which start at a few Hz and go upward to 15-20 Hz or so. At least some of these were the same LF resonances I excited with my sweep, but not all of them. This sound was present even if everyone is silent. I crunched the results of the measurements, and they were sent on to a musicologist that was part of the staff. As mentioned, he identified that there was a pattern of frequencies, which roughly form an F-sharp chord. Not all the resonances fell in the right place but many did and some repeated the pattern for many octaves. In other words, it was roughly tuned to F-sharp over many octaves. It has been suggested (by others) that the Great Pyramid is NOT a tomb at all but actually a temple of sorts and that these resonant frequencies were “designed into” the structure. While many exotic and often far-fetched properties have been ascribed to “the power of the pyramid,” I see a possible argument that some of the phenomena people experience in it may be caused by the acoustical properties that were measured. The effects of LF sound were extensively studied by various government agencies to determine the effects on humans, partly for the space program. One of the things that was discovered is that infrasound (very LF) can effect ones brain wave activity (Alpha rhythms, etc.) and other biological functions. If, as some suggest, these pyramids were constructed as a “temple” or for an initiation ritual rather than a tomb, then the LF sounds may be deliberate and have served a scared purpose — with the sound triggering and even forcing changes in brain wave state (i.e., one’s level of consciousness). Read the rest of this post 1 2 3 4 5 6 Tagged with: Acoustics Analysis Danley Sound Labs International Live Sound International Measurement Sound Reinforcement Tom Dankey · all topics Subscribe to Live Sound International Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound. Subscribe Today!