[Aztlan] Plaster and the general geology of the Yukatan Peninsula

[David Hixson]

While I have appreciated and enjoyed Wayne's posts for many years, I must reiterate my own counter-points to his views on Maya acoustics -- especially as it figures into the architecture of the Cross Group at Palenque and the Great Ball Court of Chichen Itza.

In both of these situations, it is not the decayed stucco or plaster that may have changed the acoustical properties of these venues.  It is the architecture itself.  In both cases, at least one of the opposing structures has half-fallen to become a half-vaulted reflecting shell.  In the case of the Great Ball Court, both ends of this performance gallery have fallen to become what amounts to a parabolic reflection chamber (just remember those science museums you visited as a child, and how the two parabolic reflectors allowed you to whisper to your classmate from yards away).

I hope the following text appears as it should on-list:

          xxxxxx
         x   oooo
        x    ooooo
       x     oooooo
      x      ooooooo
     x       oooooooo
     x       oooooooo
     x       oooooooo
     x       oooooooo
     x       oooooooo
     x       oooooooo
     x       oooooooo
     xxxxxxxxxxxxxxxx

The "X" blocks remain, the "O" blocks have fallen.  A mirror opposite of this half-fallen structure stands at the other end of the Great Ball Court.  The result is an unintentional whispering chamber using two opposing reflectors.

In fact, at Chichen Itza it is unlikely that very much plaster was ever used to coat the (now fallen) facades.  So, the acoustical significance of plaster in such situations is moot.  To follow Wayne's train of thought, archaeologists would have to rebuild the fallen halves of the north and south temples (not just replaster them) in order to recreate the proper acoustical effects.

That being said, it's been a while since we've heard Wayne's latest news, so I would be more than happy to see any new developments in his Maya acoustical studies.  I've often thought that Wayne and Greg Sandor (fellow listeros) should link up to conduct some VR simulations of acoustical properties (e.g., shooting a laser or other item with a known trajectory to evaluate its reflective properties depending upon the location of the FPS).  Greg could easily add or subtract the now-fallen exterior walls to determine the effect upon acoustical vectors.

Love to hear more.

-Dave