Experience working with sound gave an insight into phenomena for which there appeared to be no texts. A number of these revolved around the interaction between hardware and people. So as not to appear subjective another's experiences can be given as an example; take a Big Brother contestant, Mary (2005). During the week that Mary was a housemate, her radiomikes were replaced five times, three units being brand new, because of failure. Scrutiny of Mary's movements showed that she had not interfered with them. When tested away from Mary, each functioned perfectly. During her post-eviction interview, one radio reporter used identical mikes, one for Mary and one for himself. Mary's microphone failed so the interviewer swapped mikes which appeared to work well, until the mike nearest Mary failed. Both mikes, when tested, worked perfectly. Mary had had no physical contact with either.
A work colleague asked me to take a photo of them with their camera. We conclusively proved that the camera would not allow me to take the desired shot, any others being possible. The colleague claimed that it was clear that I was emitting a dampening field.
Camping near a waterfall adjacent to a vertical rock-face overhung with leafy trees, the sound of opera could be heard despite this not being possible, the waterfall being in a deep valley in deep country. This persisted for the entire stay. Clearly, the noise from the fall was reflected by both rock-face and trees setting up a very interesting series of interference patterns that the brain had fun interpreting. But why opera (an unknown score) complete with vocals, all of the time? A later visit proved operaless, part of the rock-face had fallen away.
"A TV programme ('Secrets of the Dead: Sounds from the Stone Age', 12/11/01, C4, UK) followed reports on Radio 4 (text from same) dealing with the phenomena of unusual sonic aspects of ancient sites that could induce strange body sensations through sound, or infrasound, as a central part of religious ritual. The dust patterns showing up standing waves in the Newgrange chamber are interesting even though the sound pressure levels that would be needed and the sustained (very even) resonance required to allow the effect to build up might have to be large.
It's not certain what number of people might fit into Newgrange, but it doesn't take many human voices to create a substantial set of decibels; think of the front-four chorus standing in front of the full chorus and full orchestra of Beethoven's Ninth, to name only one example. Perhaps "sound pressure" does not equal decibels, and reference is being made to the kinetic energy of the sound waves. Even so, 20 people, even five - even one - can be tremendously loud. And a chorus of such voices can be deafening - and more than capable of "sustained (very even) resonance", including complex harmonics and organum, etc, effects. Think of Irish tenors and Welsh choirs. It may well be that ancient British (Celtic or Pictish or whatever) musical ritual was anything but the flute-and-tabor tranquilities favoured by New Ageists and neopagans today."
Interestingly, Philips patented an efficient speaker system using only a few drive units that was capable of very interesting spatial performance. Reading the paper, one was reminded of voices in a line when looking at the speaker arrangement.
"Consider legends such as that of a daughter of one of the kings of Tiryns (Scylla) who threw stones against the walls to make them sing; the walls having been built by giants, 'twas said, by the force of song. There are other such myths about sonically-built structures that suggest that their enhancements of rituals might have been intentional. That such sites might have been built specifically for acoustic properties may have been unintentional, but given the mythic references to song-spells and the construction of buildings, perhaps not.The Jericho legend, although earthquake damage is evident, retains a similar memory. Obviously ancient rites would have often been conducted in caves, the acoustical properties of which are common and could not have gone unnoticed, especially in performance of ritual, etc.
So when building a man-made cave - a crypt or howe or temple or whatever - the use of acoustics seems to be something that the builders might well take into consideration. In a sense, perhaps, the Greek theatres are an outgrowth of this tradition, which all for being halfshells (without a backstage shell as in the Hollywood Bowl etc.) have amazing properties of resonance and amplification and consistency; and obviously the ancient northern tradition found it's own fulfillment in cathedral acoustics some millenia later.
That Newgrange, Drogheda or anywhere else megalithic has acoustical properties seems quite natural, building at that time being organic with experience, which would include the known echoing quality of enclosed places. Happenstance or stonemasons wizardry, integrated within their knowledge of ritual. Such qualities are demonstrated by the temple-builders of Malta - the Chalcolithic Goddess Temple on Malta has chambers cut into the rock which to some ears are harmonic, and obviously resonant, like singing in the shower. Arrayed around the periphery of the sacred chamber, they could all add up to a musical instrument.
In the Argonautica, Amphion and Zethus built Thebes by moving huge stones by singing with his golden lyre (I-740) while Orpheos moved the large oaks down from a mountain in Thrace with his lyre (I-25).
The Greek words mukema, mukeomai and several other variations of muke- refer to the roar of lions, bulls, and water as waves and torrents. Several Dorian settlements in the Aegean, eg Rhodes had "bull" horns, often equated to conch shells, which were used to warn locals of the approach of sea-going vessels. Mukenai (Mycenae) was situated between a torrent mapped as Xavos (Chaos), the naming of the town perhaps having some significance. The Bacchae by Euripides has allusions to bulls bellowing, hence the idea of theatres issuing potent sounds. The Argonautica says that where the Eridanus (Po) and Rhodanus (Rhone) met the water 'muxates' roared, though we know these two rivers do not meet at all."
The shape of dolmen type tombs with their characteristic capstones sloping down from the 'entrance' to a vertical rear wall appears to intend the reflection of sound caused in or aimed at the structure. It might be possible that the final position of all the stones was tuned to, say, a set of voices to give the prerequisite effect. If the lowest wavelength sustainable is related to the chambers' length then this gives some 41Hz for Tinkinswood, some 66Hz for Pentre Ifan and about 90Hz for St Lythans, say.
These acoustic qualities were probably discovered in the earlier use of caves. Much cave art is found in resonant chambers and caverns, perhaps underlining the 'magical' qualities perceived. This would explain the 'clustering' of images when other usable surfaces are ignored. Bone flutes and 'roarers' have been found in decorated caves together with images of dancers.
At all times, it must be remembered that today we see these structures in a condition close to what architects today would call 'ready for second-fixing', ie; structurally complete but without services, embellishments and decoration so we can have no idea what other organic structures might have been added that have since disappeared with time. For example, circles of timber posts may well have supported roofs. These may not have risen to a central point, but to each other. Again, even dry stone walling will have been stripped away.
Biological synchronisations can be seen, with direct comparisons as in those found in shoals of fish and flocks of birds, where rhythmic breathing patterns (in humans 6 breaths per minute seems to be significant) affect the heart, then in turn the frontal lobes and then the entire physiology which create entrainment or unity between nearby people. This can be found in football crowds, raves and can be used by dictators. The repetition of Vedic or Gregorian plain chant can 'still' the mind using a modal system that in the latter can centre around the 'ray' in 'doh, ray, me'. Recitation of the Koran is recommended in slow, even tones. Then there are the mantras like that used for Hare Krishna and Aum (the sound held by Hindus to have been present at the creation of the world). Some cosmologists now see residual Big Bang radiation as an audible signal ('the Song of the Spheres') that can interact.
Given personal experience, an interest in physiological conditions arising from exposure to fluctuating sonic or magnetic fields has thus arisen.
Other links; including The Megalithic Portal, C4s' Real Wizards and other sites discussing the possibility of the Maya dabbling in acoustics (links 1 and 2), together with an Acoustical Analysis of the Great Pyramid (includes infrasound).