Acoustic Evidence

[Michael T. Griffith]

You reject my credible, logical responses but that doesn't mean they haven't been given to you......multiple times.
Did she tell them what she saw before or after the shooting? I think we both know the answer to that. I don't know what she saw or what she thought she saw but it's easy to embellish a story to make it seem relevant to the assassination. Her story would have had far more credibility and significance had she told law enforcement about it BEFORE the assassination. That's what I meant when I said she didn't tell law enforcement. She didn't tell them before the shooting when it could have made a difference.
If credibility were a requirement for commenting on the JFK assassination, you would have been banned from every JFK assassination forum decades ago.
Your excuses made no sense.
As long as we are demanding explanations, explain why your conspirators would drive around for several minutes in a small parking lot and then leave. You are the one claiming these cars had some connection to the shooting so the burden is on you to establish that. I have no burden to prove that they were not connected. Once more you have assumed something you cannot prove.
For starters, Lee Bowers' observation that there was no gunman behind the stockade fence at the time he heard the shots.

Despite numerous people rushing to the area immediately after the shooting, no one saw a man with a rifle in the area behind the stockade fence.

There were no wounds to either JFK or JBC that were caused by a frontal shot.

So if someone fired a shot from the GK, he did so without being seen during or immediately after the shooting.
 
The vast majority of earwitnesses, regardless of where they believed the shots came from, said they heard 3 shots which matches the number of spent shell found in the sniper's nest.

The GK shooter left no spent shells.

No bullets were recovered except for the two fire from Oswald's rifle.

No wounds to either JFK or JBC caused by a shot from the GK.

You made a big deal about Oswald missing the whole limo with his first shot. Apparently your GK shooter did the same.
The following website give a good summation of the arguments for an against the acoustic evidence showing a GK shooter. The following passage sums up the situation fairly succinctly:

"Sources do not provide a single, universally accepted resolution; expert opinion remains divided and many critiques focus on timing, statistical assumptions and recording artifacts rather than on the raw waveform matches alone."

Notice I did not resort to MTG's practice of clipping a few words out of context. I quoted an entire sentence and provided a link to the entire article for others to judge.

I've already proved to you in numerous exchanges in this forum that every one of these arguments is either false or misleading or irrelevant. And I notice you again made no effort to explain the facts that validate the HSCA's acoustical findings.

Let's try this: How about if you just answer one straightforward question? Here it is:

If the dictabelt did not record gunfire in Dealey Plaza during the assassination, how did N-waves get on the dictabelt -- not crude, superficial N-waves from random noise but gunfire N-waves with muzzle blasts and muzzle-blast echoes, in the correct order and interval, and only when the microphone was in position to record them?

I'll even give you a big hint: The NRC/NAS panel did not even mention the N-wave evidence, much less try to explain it, even though they knew it was a major item of evidence that the HSCA's acoustical scientists justifiably cited as powerful support for their findings.

Ah, heck, I'll give you another big hint: The Linsker group (Linsker, Garwin, Chernoff, Horowitz, and Ramsey) that responded to Dr. Thomas's 2001 article on the acoustical evidence did not lay a finger on the N-wave evidence either, even though four of them had served on the NRC/NAS panel and thus were well aware that this was a major item of evidence that the panel had ignored.

I'll even give you some study notes to help you answer the question.

Dr. David Scheim, who holds a doctorate in mathematics from MIT:

Moreover, an "N-wave," characteristic of supersonic gunfire, appeared in each dictabelt impulse for which the police microphone was in an appropriate position to detect it, including the recorded sound of the third shot [i.e., 144.9 impulse pattern/the grassy knoll shot]. (The Mafia Killed President Kennedy, 1988, pp. 27-28)

Dr. G. Paul Chambers, a physicist who has worked with NASA, with the Naval Surface Warfare Center, and with the Naval Research Laboratory:

In Dealey Plaza, echoes from gunshot test patterns arrive in two discrete [different] clusters, differing in time by about 190 ms. Echoes originating from structures along Elm Street arrive within 85 ms, while echoes from structures farther back on Houston Street arrive in the last 95 ms of a typical 370-ms-duration test pattern. In addition, a “muzzle blast” is usually prominent at the beginning of a gunshot acoustical pattern, while an N-wave (a shock wave traveling faster than the speed of sound due to the rifle bullet exceeding the sound barrier) arrives prior to the muzzle blast. The waveform identified as the grassy knoll shot is shown in figure 13. The presence of an N-wave in this waveform was consistent with the acoustical signature of a supersonic rifle bullet. (Head Shot: The Science Behind the JFK Assassination, 2010 pp. 101-102)

[John Corbett]

I've already proved to you in numerous exchanges in this forum that every one of these arguments is either false or misleading or irrelevant.

You've declared that many times. We have yet to see the proof.

And I notice you again made no effort to explain the facts that validate the HSCA's acoustical findings.

Unlike you, I don't pretend to be an expert in all these highly technical fields pertaining to the JFKA. i've seen how foolish you make yourself look when you try,

Let's try this: How about if you just answer one straightforward question? Here it is:

If the dictabelt did not record gunfire in Dealey Plaza during the assassination, how did N-waves get on the dictabelt -- not crude, superficial N-waves from random noise but gunfire N-waves with muzzle blasts and muzzle-blast echoes, in the correct order and interval, and only when the microphone was in position to record them?

There are no muzzle blasts on the Dictabelt recording. That much I do know. I know what a muzzle blast from a rifle sounds like and it sounds nothing like the impulses on the recording.

I'll even give you a big hint: The NRC/NAS panel did not even mention the N-wave evidence, much less try to explain it, even though they knew it was a major item of evidence that the HSCA's acoustical scientists justifiably cited as powerful support for their findings.

Apparently, they too recognized those weren't muzzle blasts.

Ah, heck, I'll give you another big hint: The Linsker group (Linsker, Garwin, Chernoff, Horowitz, and Ramsey) that responded to Dr. Thomas's 2001 article on the acoustical evidence did not lay a finger on the N-wave evidence either, even though four of them had served on the NRC/NAS panel and thus were well aware that this was a major item of evidence that the panel had ignored.

They also didn't hear muzzle blasts.

I'll even give you some study notes to help you answer the question.

Dr. David Scheim, who holds a doctorate in mathematics from MIT:

Moreover, an "N-wave," characteristic of supersonic gunfire, appeared in each dictabelt impulse for which the police microphone was in an appropriate position to detect it, including the recorded sound of the third shot [i.e., 144.9 impulse pattern/the grassy knoll shot]. (The Mafia Killed President Kennedy, 1988, pp. 27-28)

Dr. G. Paul Chambers, a physicist who has worked with NASA, with the Naval Surface Warfare Center, and with the Naval Research Laboratory:

In Dealey Plaza, echoes from gunshot test patterns arrive in two discrete [different] clusters, differing in time by about 190 ms. Echoes originating from structures along Elm Street arrive within 85 ms, while echoes from structures farther back on Houston Street arrive in the last 95 ms of a typical 370-ms-duration test pattern. In addition, a “muzzle blast” is usually prominent at the beginning of a gunshot acoustical pattern, while an N-wave (a shock wave traveling faster than the speed of sound due to the rifle bullet exceeding the sound barrier) arrives prior to the muzzle blast. The waveform identified as the grassy knoll shot is shown in figure 13. The presence of an N-wave in this waveform was consistent with the acoustical signature of a supersonic rifle bullet. (Head Shot: The Science Behind the JFK Assassination, 2010 pp. 101-102)

Being a mathematician or a physicist does not qualify one as an expert in acoustics. What we have are conflicting opinions of people who are experts as to whether the Dictabelt recording is of gunshots fired during the assassination. Jurors in both civil and criminal cases are often presented with conflicting expert testimony. They are tasked with determining which side has presented the more credible expert testimony. One of the ways they have of doing that is determining which viewpoint fits the body of evidence as a whole. There is absolutely no other credible evidence of a gunshot on the GK. No bullets were recovered except for the two fired by Oswald's rifle. No discarded shells were found except for the three in the sniper's nest which was on the same floor as Oswald's rifle which was positively matched to the only recovered bullets and shells. Neither JFK nor JBC were hit by shots fired fro anywhere in front of them. A witness with a perfect view of the area behind the stockade fence didn't see a shooter at any time before, during, or after he heard the shots. Neither did any of the people who raced to that area following the shots. In short, their is no credible evidence to corroborate the opinion that the Dictabelt recorded gunshots during the shooting. That makes it easy for me to decide whether to believe the experts who said the recording was of gunshots or the experts who said it was not.