Acoustic Evidence

[Phil Sanders]

New here.  Can someone please direct me to on this forum or explain the apparent contradiction that J. Thompson uses acoustic evidence in his book, The Last Second in Dallas,  and the previous work that claims to debunk the Dictabelt recordings. Thanks.

[Michael T. Griffith]

New here.  Can someone please direct me to on this forum or explain the apparent contradiction that J. Thompson uses acoustic evidence in his book, The Last Second in Dallas,  and the previous work that claims to debunk the Dictabelt recordings. Thanks.

I address the attacks on the acoustical evidence in my article "The HSCA’s Acoustical Evidence: Proof of a Second Gunman in the JFK Assassination".

By "the previous work that claims to debunk the Dictabelt recordings," I'm guessing you're referring to the NRC/NAS panel's critique of the acoustical evidence. The panel, aka the Ramsey Panel, did not include a single acoustical scientist, and virtually their entire case rested on the debunked claim that the Decker "hold everything" transmission was crosstalk and that the transmission proved the sound impulses were recorded 30-60 seconds after the shots were fired.

Dr. Thompson arranged for new research by BBN acoustical scientists from 2015-2018 that refuted the NRC claim about Decker's transmission and that verified that the Fisher "I'll check" transmission is actual crosstalk and that it proves the sound impulses were recorded during the shooting. He discusses this new research at length in Last Second in Dallas. Two BBN acoustical scientists wrote appendices in Thompson's book.

Also, it's worth noting that the NRC/NAS panel admitted (as obliquely as possible) (1) that they found a 93% probability that the timing-movement correlations identified by the BBN scientists between the dictabelt and the recording of the test firing in Dealey Plaza occurred because the dictabelt recorded gunfire in Dealey Plaza, and (2) that they found a 77.7% probability that the 144.9 impulse pattern, identified by Weiss and Aschkenasy as gunfire from the grassy knoll, was in fact gunfire from the knoll. You'll notice that critics of the acoustical evidence never, ever deal with this fact.

See also the following:

https://www.maryferrell.org/arch/essays/debugging-bugliosi

https://www.maryferrell.org/arch/essays/bike-with-the-mike

https://www.maryferrell.org/arch/essays/sabato-sonalysts-sophistry

https://www.maryferrell.org/arch/essays/overview-and-history-of-acoustical-evidence-1

Another excellent analysis of the acoustical evidence is Dr. David Kaiser's lengthy discussion on the subject in his highly acclaimed book The Road to Dallas (pp. 377-387).

And you might find this discussion helpful:

https://educationforum.ipbhost.com/topic/29269-understanding-and-appreciating-the-hsca-acoustical-evidence/

My signals intelligence training in the Army included courses on radio wave propagation, modulation, the effects of automatic gain control, RF theory, the electromagnetic spectrum, etc. I don't claim to be an acoustical scientist, but I know more about the subject than your average Joe.

[John Corbett]

The claim that the acoustics evidence found on the Dictabelt recording shows a fourth shot has been thoroughly debunked in so many ways. The following is as good as any:
 
https://www.jfkfiles.com/jfk/html/acoustics_2.htm

Going to the homepage will also give you access to Dale Myers 3D animation of the shooting.

[Michael T. Griffith]

The claim that the acoustics evidence found on the Dictabelt recording shows a fourth shot has been thoroughly debunked in so many ways. The following is as good as any:
 
https://www.jfkfiles.com/jfk/html/acoustics_2.htm

Going to the homepage will also give you access to Dale Myers 3D animation of the shooting.

The sources I cite in my reply refute every single criticism presented in the article you cite, Dale Myers' article. You'd know this if you'd bothered to read the links I provided. If you had just read my article on the acoustical evidence, you'd know that Myers' article is woefully inadequate and misleading.

And for the benefit of other readers, be advised that Dale Myers' research has been proven to be erroneous, if not fraudulent. As just one example, to make his ridiculous SBT trajectory analysis work, Myers falsely assumes that Connally's back wound was 3.0 cm wide, when in fact it was only 1.5 cm wide, the same width as JFK's rear head entry wound.

For a good critique of some of the problems with Myers' bogus research, see the uber-cautious Pat Speer's demolition of Myers' SBT nonsense:

https://www.patspeer.com/chapter12canimania

Here is just a little bit of what Speers says about Myer's SBT simulation:

. . . his deception regarding the single-bullet theory is simply inexcusable. He would have to know that when people see computer simulations they believe the proportions are consistent from angle to angle—otherwise it’s just a cartoon. By changing the body shape of Kennedy to accommodate the bullet trajectory through his body, and by shrinking Connally 20% or more to accommodate the bullet trajectory in the car, Myers moved on up to the high rent neighborhood of Thomas Canning: deliberate deceptionville.

For a critique of Myers' error-riddled hatchet job on the Tippit shooting, see my article "Did Oswald Shoot Tippit?"

It says much that you would rely on someone like Myers to get your information on the acoustical evidence. Have you even read the studies that the BBN and Queen's College acoustical scientists submitted to the HSCA on the acoustical evidence?

Myers obviously hasn't read them, because he doesn't say a word about any of the evidences they present, such as the windshield-distortion correlations, the timing-movement correlations, and the presence of N-waves and their echoes in the correct order and timing. Nor does Myers say a word about the NRC/NAS panel's admissions about the timing-movement correlations and their own finding of a high probability (77.7%) that the 144.9 impulse pattern is gunfire from the grassy knoll.

[Steve Barber]

New here.  Can someone please direct me to on this forum or explain the apparent contradiction that J. Thompson uses acoustic evidence in his book, The Last Second in Dallas,  and the previous work that claims to debunk the Dictabelt recordings. Thanks.

Hello Mr. Sanders.

I hope to try to give you an understanding of Thompson's research for his acoustics chapter within the following. Thompson bases his conclusions of the acoustics on the careless research by Donald Thomas (R.I.P.), whom you no doubt read about in Thompson's book. 

I am sure that you're now familiar with a Don Thomas after reading the acoustics chapter in "Last second in Dallas".  It is his "analysis" of the acoustics and the 2 channels made by the Dallas police department 11/22/1963, channel 1, the Dictabelt recording and channel 2, the grey audograph disc.  Thomas, like everyone, analyzed the recordings after they were transferred onto magnetic tape in 1964 by Dallas police communications supervisor James C. Bowles.

I am attaching a piece that I wrote in 2007-part of what was published in Vincent Bugliosi' Reclaimng History book, and also a revised edition also in 2007, on the Dale Myers website titled "Secrets of a Homicide", regarding Don Thomas' attack on Vince Bugliosi and myself , claiming that we were both "Bamboozled". Nothing could be further from the truth.

 I am attaching the link to my article, below.  The article will explain why Don Thomas' theory holds no water, based upon a transmission he heard on channel one 3 seconds before the so called first "gunshot" recorded on the Dictabelt, which I mentioned above

 I hope this helps you in some way to get a better understanding the conclusions reached by Thompson in his book, and how they are completely wrong regarding the "gunshot evidence". 

 https://jfkfiles.blogspot.com/2007/07/of-crosstalk-and-bells-rebuttal-to-don.html

[John Corbett]

The sources I cite in my reply refute every single criticism presented in the article you cite, Dale Myers' article. You'd know this if you'd bothered to read the links I provided. If you had just read my article on the acoustical evidence, you'd know that Myers' article is woefully inadequate and misleading.

They disagree with Myers. They don't refute Myers. Myers got it right. Your sources got it wrong. Not surprising you gravitated toward them.

And for the benefit of other readers, be advised that Dale Myers' research has been proven to be erroneous, if not fraudulent. As just one example, to make his ridiculous SBT trajectory analysis work, Myers falsely assumes that Connally's back wound was 3.0 cm wide, when in fact it was only 1.5 cm wide, the same width as JFK's rear head entry wound.

MTG has a very strange idea of what constitutes proof. Repeating the same myths over and over again is not proof.

For a good critique of some of the problems with Myers' bogus research, see the uber-cautious Pat Speer's demotion of Myers' SBT nonsense:

https://www.patspeer.com/chapter12canimania

Not at all surprising that one knucklehead would cite another knucklehead.

Here is just a little bit of what Speers says about Myer's SBT simulation:

. . . his deception regarding the single-bullet theory is simply inexcusable. He would have to know that when people see computer simulations they believe the proportions are consistent from angle to angle—otherwise it’s just a cartoon. By changing the body shape of Kennedy to accommodate the bullet trajectory through his body, and by shrinking Connally 20% or more to accommodate the bullet trajectory in the car, Myers moved on up to the high rent neighborhood of Thomas Canning: deliberate deceptionville.

A claim without proof.

For a critique of Myers' error-riddled hatchet job on the Tippit shooting, see my article "Did Oswald Shoot Tippit?" 

If your critique is on par with all the other stuff I've read from you over the past 35 years, it's not worth the time it would take to read it.

It says much that you would rely on someone like Myers to get your information on the acoustical evidence. Have you even read the studies that the BBN and Queen's College acoustical scientists submitted to the HSCA on the acoustical evidence?

Myers obviously hasn't read them, because he doesn't say a word about any of the evidences they present, such as the windshield-distortion correlations, the timing-movement correlations, and the presence of N-waves and their echoes in the correct order and timing. Nor does Myers say a word about the NRC/NAS panel's admissions about the timing-movement correlations and their own finding of a high probability (77.7%) that the 144.9 impulse pattern is gunfire from the grassy knoll.

A lot of technobabble that proves nothing. There was no shooter on the GK. Anyone who believes that has been hoodwinked by junk science. The Dictabelt recording in question wasn't even made during the shooting. The acoustics "evidence" is all the CTs have going for them and they are going to cling to it no matter how much it has been debunked.

[Michael T. Griffith]

Hello Mr. Sanders.

I hope to try to give you an understanding of Thompson's research for his acoustics chapter within the following. Thompson bases his conclusions of the acoustics on the careless research by Donald Thomas (R.I.P.), whom you no doubt read about in Thompson's book. 

I am sure that you're now familiar with a Don Thomas after reading the acoustics chapter in "Last second in Dallas".  It is his "analysis" of the acoustics and the 2 channels made by the Dallas police department 11/22/1963, channel 1, the Dictabelt recording and channel 2, the grey audograph disc.  Thomas, like everyone, analyzed the recordings after they were transferred onto magnetic tape in 1964 by Dallas police communications supervisor James C. Bowles.

I am attaching a piece that I wrote in 2007-part of what was published in Vincent Bugliosi' Reclaimng History book, and also a revised edition also in 2007, on the Dale Myers website titled "Secrets of a Homicide", regarding Don Thomas' attack on Vince Bugliosi and myself , claiming that we were both "Bamboozled". Nothing could be further from the truth.

I am attaching the link to my article, below.  The article will explain why Don Thomas' theory holds no water, based upon a transmission he heard on channel one 3 seconds before the so called first "gunshot" recorded on the Dictabelt, which I mentioned above

I hope this helps you in some way to get a better understanding the conclusions reached by Thompson in his book, and how they are completely wrong regarding the "gunshot evidence". 

https://jfkfiles.blogspot.com/2007/07/of-crosstalk-and-bells-rebuttal-to-don.html

Mr. Sanders, I would actually encourage you to read the sources that Steve Barber cites, in addition to reading the sources that I've cited. If you do, you will see that Barber's sources do not even address the main points of evidence that support the findings of the HSCA's acoustical scientists.

One of the most frequently cited attacks on Dr. Thompson's 100-plus-page presentation on the acoustical evidence in his book Last Second in Dallas is a 14-page critique written by Louis Girdler, writing under the pseudonym "Premier Kissov." If you read it, you'll notice that Girdler says absolutely nothing about the new BBN research (such as Dr. Richard Mullen's PCC testing of the Decker transmission, which proves it is an overdub and not crosstalk), and says nothing about the impossible recording-pause theory, which was the crucial assumption of the debunked Decker-crosstalk argument ("'Your Lying Eyes'--Josiah Thompson's Lonely Labrinth: A Critical Review of 'Last Second in Dallas,'" pp. 27-40, published on the Kennedy Assassination Home Page, a pro-Warren Commission website).

Instead, Girdler simply rehashes some of the arguments made (1) by the NRC/NAS panel, (2) by Anthony Pellicano (who actually accidentally provided strong evidence against the recording-pause theory and provided evidence that the bell sound on the dictabelt does not prove it was not recorded in Dealey Plaza during the shooting), (3) by the FBI's Technical Services Division (who employed no acoustical scientists and proved they didn't even understand how N-waves can be identified in audio recordings), (4) by some Sonalyst analysts (who didn't even understand how AGC works), and (5) by amateurs such as Jim Bowles and Michael O'Dell.

The foundational assumption of the argument that the Decker transmission proved the impulse patterns on the dictablet were recorded after the assassination was the specious (and now debunked) assumption that Channel 2 on the dictabelt stopped recording for 31 to 60 seconds.

As several scientists pointed out years ago, for this recording-pause theory to even be theoretically possible, there would have to be an offset in the dispatcher time notations on the dictabelt after that point, but there is none. The 12:35 and 12:36 time notations occur exactly five and six minutes respectively after the 12:30 time notation. The NRC/NAS failed to explain this fact, as did Linsker, Garwin, Chernoff, Horowitz, and Ramsey in their 2005 rebuttal to Dr. Don Thomas's 2001 article on the acoustical evidence.

You would think that any critical review of Thompson's book would deal with the historic new BBN research on the acoustical evidence, especially the two appendices written by Dr. Barger and Dr. Mullen, but Girdler says nothing about any of this. Girdler also says nothing about the NRC/NAS panel's admissions about the high probabilities of the timing-movement correlations and the grassy knoll shot, nor about the windshield-distortion correlations.