There were significant sounds recorded on audio at the beginning of the Plasco collapse and they were analyzed and shown to have the pressure pulse form of explosive noise and not that of impact noise. There is a difference which you can see on pdf page 26 in the paper Fundamentals of Acoustics by Colin Hansen hereYou're almost there. People were recording the plasco collapse from very, very close by. The absence of any detectable explosive sounds in fact indicates the absence of any high explosives. You need to find another explanation for the expulsions, such as floors collapsing variously in a fire-induced progressive collapse.
These pulses also seem to be too close together to have been from falling and impacting floors. The time between the seven pulses, measured over a 511 millisecond period, at the beginning of the collapse, ranges from 40 to 120 milliseconds, varying randomly, with no regular pattern of getting shorter as time went on.
http://www.ae911truth.org/images/PDFs/Plasco_Building_Report_2.20.17.pdfTable 1 below shows (1) the time of each impulse in the video, (2) the interval between each impulse, and (3) the cumulative time elapsed since the first impulse. Figure 6 is a visualization of the audio analysis.
The occurrence of seven separate impulses is consistent with video of the south face taken directly from the south,12 which does not show an explosion emanating from one point. Rather, it shows a number of explosions emanating along the same floor from the center of the south face to the east side of the south face.
The audio analysis application Photosounder was used to conduct an analysis of the audio from this video: Source: https://youtu.be/0jz-GXXkxI8
Last edited by a moderator: