[Aztlan] Plaster and Echoes

Tue Sep 9 10:16:12 CDT 2008

Paul,

My son experimented with the echo from two different distances from the front of the pyramid. He had to estimate the distance using a compass because INAH would not allow him to use a tape measure (he needed a permit). I don't recall what those estimated distances were, but will contact him for the  paper he wrote about his experiment.

That said, here's an anecdote to support his results: We originally attempted his experiment on the west side of El Castillo, but couldn't because workmen were digging with picks at the Platform of the Eagle and Jaguars. Every time a pick hit the hard, baked earth, the pyramid would chirp. You could only hear the chirp if you were southwest of the stairway, and only within a very narrow band. From the staircase, the Platform is to the northwest. Again, this supports that the chirp is an echo from the staircase (although we took no exact measurements), and that even if the sound is originating a couple hundred feet away there is still a relatively narrow angle of reflection.

However, it is my son who is the scientist, not me. Take it for what it is.

Regards,

-- Evan

----- Original Message ----
From: Paul Troemner <troemner at yahoo.com>
To: David Lubman <dlubman at ix.netcom.com>; D. Clark Wernecke <CWernecke at compuserve.com>; Greg Sandor <gregory_sandor at hotmail.com>; EJ Albright <vanjayal at yahoo.com>
Cc: Aztlan <aztlan at lists.famsi.org>; D. Clark Wernecke <102402.2332 at compuserve.com>
Sent: Tuesday, September 9, 2008 9:35:06 AM
Subject: Re: [Aztlan] Plaster and Echoes

Evan,

But how far was your son from the stairs, and from the 9 platforms?  I think with the 9 walls and the 91 stairs, as long as both groups have vertical or near-vertical surfaces, and the clapping individual is far enough back from the structure, there will be some echo or response from either stairs or walls, whether you get a chirp, or a series of shortly spaced clap responses.

For the nine walls, there is probably a "sweet spot" distance required to get the chirp.  Too close, and you can't get the echo except off the first tier, and that may be too small of a time lapse to differentiate from the clap.

The stairs may work even close up, but for the walls to work, there needs to be a certain distance between the clapping individual and the pyramid.  It's a function of wall height and individual stair height.

I agree, there needs to be a lot more testing.  It may be that the stairs are for close-up clapping, and the 9 walls are for more distant.  I don't think the stairs will return a snake rattle echo (from a single hard loud rattle shake) like the 9 walls will.

Thanks for the message.

Paul

--- On Mon, 9/8/08, EJ Albright <vanjayal at yahoo.com> wrote:

> From: EJ Albright <vanjayal at yahoo.com>
> Subject: Re: [Aztlan] Plaster and Echoes
> To: troemner at yahoo.com, "David Lubman" <dlubman at ix.netcom.com>, "D. Clark Wernecke" <CWernecke at compuserve.com>, "Greg Sandor" <gregory_sandor at hotmail.com>
> Cc: "Aztlan" <aztlan at lists.famsi.org>, "D. Clark Wernecke" <102402.2332 at compuserve.com>
> Date: Monday, September 8, 2008, 10:31 PM
> The sound is produced by the stairs. Last fall, my
> 17-year-old son performed an experiment at El Castillo to
> determine where the echo originated. If you stand directly
> in front of the staircase and clap, you hear the chirping
> echo. If you stand at a 30-degree angle from the stairway,
> directly in front of the nine platforms, and you clap, you
> hear nothing. However, someone else standing at a 30-degree
> angle on the opposite side of the staircase hears the
> chirping echo.
> 
> He continued to experiment until he was able to determine
> with some certainty that the echo was originating from the
> staircase.
> 
> I'm not sure what grade his physics teacher gave him,
> but I was impressed.
> 
> Cheers!
> 
> -- Evan J. Albright
> 
> 
> 
> 
> 
> ----- Original Message ----
> From: Paul Troemner <troemner at yahoo.com>
> To: David Lubman <dlubman at ix.netcom.com>; D. Clark
> Wernecke <CWernecke at compuserve.com>; Greg Sandor
> <gregory_sandor at hotmail.com>
> Cc: Aztlan <aztlan at lists.famsi.org>; D. Clark
> Wernecke <102402.2332 at compuserve.com>
> Sent: Monday, September 8, 2008 11:23:20 AM
> Subject: Re: [Aztlan] Plaster and Echoes
> 
> > Can someone please describe how the "chirp"
> is
> > produced?
> 
> Greg,
> This is my theory (there are other theories out there):
> 
> There are 10 near-vertical walls on the structure:  9 for
> the steps in the pyramid, and one at the building on top. 
> The chirp is made of 10 echos of the clap, each just
> slightly delayed from the previous echo, and slightly weaker
> (an increase of distance and reflecting angle and a decrease
> in reflective wall area as you go up the pyramid).
> 
> David Lubman says the chirp is 0.2 seconds long (I had
> guessed it was half second, but he had measured it).  I
> would guess the 10 echoes are compressed into that 0.2
> seconds, which gives it a "grainier" sound than
> the Quetzal chirp (10 vibrations instead of 400 or some
> other number).  David has theorized that it is the stairs
> causing the chirp, but the near-vertical surface area of the
> stairs is smaller than the near-vertical surface area of the
> pyramid steps (I'll refer to stairs as the stone
> staircase, and steps as the 9 steps of the pyramid).  The 91
> stairs may contribute part of the sound, but with smaller
> echoes closer together.
> 
> >From
> http://www.world-mysteries.com/chichen_kukulcan.htm#Statistics
> 
> The stairs' vertical area 8.85 m x 24 m, or 212 meters
> squared, is less than the pyramid steps' vertical area
> 686 meters squared (plus the building on top, 13.42 m x 6 m
> high on narrower side, or an additional 81 meters squared,
> for 767 meters squared total).
> 
> I think the stairs contribute about 1/4 of the echo effect,
> and the pyramid steps the other 3/4.  The pyramid steps,
> contributing the most, would be more likely to return a
> snake rattle sound from a single shake of a rattle, but this
> theory for the snake rattle has not been tested.  Another
> test would be to point a parabolic microphone at the one
> location at a time (5th step or 25th stair, etc.) on the
> pyramid during the clap and response.
> 
> I think that even if we do find out how the chirp is
> generated by the structure, and if we believe it was
> intended by the builders, how did they come up with the
> design?  Was it theoretical accoustic design (using the
> speed of sound, math, and so forth), empirical accoustic
> design (trial and error through earlier structures), or a
> combination of both?  Has anyone observed the angle a
> rattlesnake makes when shaking its tail?  Are the 10 cycles
> representative of 10 rattles on a snake, with the building
> on top representing the initial bead of the snake?  Are the
> various stepped pyramids in Palenque, Copan, and elsewhere
> earlier prototypes of the chirping design?
> 
> Continuing with the idea that there are potentially light
> and sound shows from this structure, we are aware of the
> snake light show, the quetzal sound show, and potentially a
> snake sound show.  That leaves a quetzal light show as yet
> undiscovered?  Why is there a rectangular building (instead
> of square) on top of a nearly square pyramid?
> 
> I thought I heard that the unrestored faces of the pyramid
> have been reported to return a similar "chirp" as
> the restored face of the pyramid.  If the stones or debris
> on the unrestored faces have at least some vertical surfaces
> or near-vertical surfaces, a response of some sort will be
> generated, but probably not as distinct as the 10-cycle echo
> of the restored face, and will scatter the single rattle too
> much to make a snake rattle return.
> 
> Paul Troemner
> 
> --- On Sat, 9/6/08, Greg Sandor
> <gregory_sandor at hotmail.com> wrote:
> 
> > From: Greg Sandor <gregory_sandor at hotmail.com>
> > Subject: Re: [Aztlan] Plaster and Echoes
> > To: "David Lubman"
> <dlubman at ix.netcom.com>, "D. Clark Wernecke"
> <CWernecke at compuserve.com>
> > Cc: "Aztlan" <aztlan at lists.famsi.org>,
> "D. Clark Wernecke"
> <102402.2332 at compuserve.com>
> > Date: Saturday, September 6, 2008, 12:36 AM
> > Can someone please describe how the "chirp"
> is
> > produced?
> > 
> > Regards,
> > 
> > Greg
> > 
> > (614) 517-7204
> > greg at gregsandor.com
> > http://www.gregsandor.com
> 
> 
> 
>      
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