bernard Wrote:
-------------------------------------------------------
> WVK Wrote:
> --------------------------------------------------
> -----
> > bernard Wrote:
> >
> > Are you claiming that a handclap in front of the TofW produces a QUETZAL chirp? The
> > Video certainly did not produce the same chirp as the Castillo when the guide clapped
> > his hand.
> >
> > I am not aware of a video that captures the sound of the chirp
> > from the TofW. My recollection is that it was
> > similar in character to El Castillo.
>
> Look at the video you posted. The guide also claps
> his hands in front of the T of W-- no chirp and no
> serpent hiss is produced

Bernard, you are misinformed and jumping to false conclusions. You also disregard reports by people who have heard the serpent hiss. Are you suggesting that these ear-witnesses are lying or halucinating? You may not disregard verifiable evidence without reason.

You were so anxious to dismiss these reports that you failed to make even minimal inquiries into where the observers were standing. Are you sure the cameraman was standing at an appropriate location to hear the chirp AND the hiss?

Imagine a vertical plane cutting through castillo along the center line of the north staircase. To hear the chirp observers/listeners must stand on the ground within an angular sector about +/- 30 degrees wide on a plane passing through the staircase centerline.

Let an observer clap while standing on a center line facing the temple. The sound disturbance propagates nearly omnidirectionally in the horizontal plane. That means the disturbance strikes the north staircase but also strikes the TotC (Temple of 1000 columns).

If the observer is not too far from the pyramid base, the first echo heard will be the chirp from the pyramid's north staircase. It's heard first because the sound's round trip path is shortest. The next sound event is scattered returns from the TotC. That's because its round trip path is greater.

Suppose the path length difference for the two echoes is 200 m. The first scattered returns from the TotC are heard about 200/343 = 0.58 sec after the start of the chirped echo. The chirp persists for about 0.1 sec. So scattered returns from the TotC are in the clear. (Those returns will be heard to come from a different direction.)

What will scattered returns from the TotC sound like?

It will certainly be time dispersed (stretched out in time). That's because sound scattered from each column strikes a nearby column, is scattered again, and so on. This "multiple scattering" process persists much longer than the brief handclap. Will it sound like a serpent's hiss? That's what listeners report.

Evidently that sound has a lot of high frequency energy. But because of high-frequency hearing loss I could not hear it. (My audiograms drop sharply above about 2500 Hz)

This is the "sonic crystal" problem about which Bernard was so dismissive. It's a daunting problem to solve analytically. I think it quite possibly could sound like a high frequency serpent hiss.

Even if the problem cannot be solved analytically, it can be heard, it can be tested on scale models, it can be simulated on a computer.

FYI, here's a report by science writer Phillip Ball about sonic crystals. [www.science.org.au]

In the last three paragraphs he connects sonic crystals with my work at Chichen Itza. Since then, these Spanish investigators and other research teams have determined that sonic crystals can create "cloaks of invisibility" to prevent submarines from being detected by sound, and photonic crystals that can make objects invisible. This is absolutely world-beating physics.

Those facts are only indirectly related to our topic. But I suggest that Bernard, with all his knowledge and skills, is probably incapable of imagining the sophisticated sound effects that periodically spaced steps, columns, or other objects can produce.

From the quoted article:

"Could the Mayans really have known the secret of sonic crystals as long as 900 years ago? "I think the answer is yes," says Francisco Meseguer. Sánchez-Dehesa agrees: "We can say that the Maya are the first people to harvest sound by making a sonic crystal." And he hopes to prove it with a series of experiments at the pyramid. We may soon know whether the quetzal bird sings at Chichén Itzá by chance or design."