Thompson's New Book Powerfully Confirms the HSCA Acoustical Evidence

[Michael ODell]

Dr. Thompson's approach is to show that the dictabelt recording absolutely, positively contains at least four gunshot impulse patterns that were recorded in Dealey Plaza during the assassination, and that one of the shots came from the grassy knoll. So someone's microphone in Dealey Plaza recorded those gunshots, whether it was McClain's, Beilharz's, Price's, or someone else's mike. Personally, I find Dr. Thomas's research on the bike with the mike convincing. 

Dr. Thompson?

This is not true.  The book contains no proof that four gunshots are on the recording.  It doesn't even claim to prove that.  It simply assumes that previous work showed that.

The gunshot impulse patterns match the unique patterns of gunshots fired in Dealey Plaza. They have the echo speed and locational characteristics of shots that were fired in Dealey Plaza and that were recorded by a motorcycle moving in Dealey Plaza. Dr. Aschkenazy put it this way:

No, they aren't unique matches.  Don't forget, BBN threw out matches because they were impossible shooting trajectories.  So if a match is a unique proof, how can throwing any out be justified?  It's because BBN knew that simply getting match the way they did doesn't prove anything,  and they never claimed it did.

I think it would be helpful to keep in mind that even the NRC panel admitted that there was only a 7% probability that the numerous locational correlations between the dictabelt gunshots and the test-firing gunshots were the result of chance (https://miketgriffith.com/files/hscaacous.pdf, pp. 12-13).

It wasn't random chance.  That doesn't mean there was gunfire.

[Michael T. Griffith]

You've gotten a little over excited.  Thompson has made claims.  They are subject to error, and are mostly wrong.

No, Thompson generally misrepresents what the NRC report says, and there was no rigging of the PCC test.  The PCC test showed CHECK was not crosstalk.  It still does.

He has not proven the CHECK is crosstalk.  He acts like he has, but doesn't actually have the goods there.  Mullen's PCC test actually proves the opposite, for reasons that will be explained later.  There is no proof anywhere in the book that the impulses occurred during the assassination.

Bowles noted CHECK as a crosstalk, and the NRC panel tested the possibility and found that it was not.  There was no concealment.  There was no reason to knowingly include Bowles' error in their transcript, and the transcript wasn't the evidence.  The recordings are the evidence.

Again, these are claims.  They are wrong.  Provably so, and that will be shown.

He does no such thing.  He wants to think so, and tries to cast doubt on it, but no such proof is in the book.

There was no expectation that they would publish Barger's letter in their report, and Barger's letter didn't contain anything that would debunk what the panel found.

Wow, I see why McAdams loves you as a source. Your claims are erroneous. I will simply leave it to each reader to compare your comments about Thompson's acoustics chapters with the acoustics chapters themselves. People like you will never admit that the acoustical evidence proves at least four shots were fired at JFK.

[Michael ODell]

Wow, I see why McAdams loves you as a source. Your claims are erroneous. I will simply leave it to each reader to compare your comments about Thompson's acoustics chapters with the acoustics chapters themselves. People like you will never admit that the acoustical evidence proves at least four shots were fired at JFK.

That is an irrational response.  I spoke the truth.  If Thompson disagrees with me that does not mean I'm the one that's wrong.  Same goes if you disagree with me.  If you actually have a reasonable argument to make, do so.

[Michael ODell]

The lone exception is the interval between the putative "I'll check it" crosstalk and the HOLD crosstalk. Between these two points, channel 2 gains about 80 seconds on channel 1. Channel 1 is running continuously at this point, so there is no way that channel two could gain time on channel 1 here. That makes "I'll check it" the outlier. If any external signal was somehow dubbed into the recordings, it's the channel one "I'll check it."

This right here.  Of course I pointed out that they were requiring channel 1 to lose time, and the fix became to postulate really absurd speed warps on channel 2.

Mullen's critique of the NAS panel's use of PCC is more complex, but it revolves around the use of time scaling various bits of the recordings. Barger and Mullen say that there are multiple overlapping bits of power supply hum in the recording, so choosing which one (or which combination) to use for proper scaling and where to apply it looks to be a significant issue, and probably will be argued about quite a bit in higher circles.

It's worse than that.  Note that Mullen's PCC result requires a 1.15 time scaling, on a recording that they've elsewhere agreed is already running at the correct speed.  It falsifies itself.

However, PCC is not the only issue that  the NAS panel raised with the alleged Fisher crosstalk. They also noted that the supposed "I'll check it" transmission is accompanied by heterodyning, indicating that this particular transmission was native to channel one. The heterodyning occurs when two transmitters attempt to transmit at the same time and interfere with each other. In this case, someone tried to transmit a message while the radio on the open mike bike was transmitting the sweet rumble of Harley Davidson. Crosstalk wouldn't generate a heterodyne like that. No heterodyning accompanies Fisher's channel 2 transmission, nor is there good reason to expect it to, so there is no reason to expect that the heterodyne was carried over from channel 2 to channel one. So far as I've read, I see no mention of this problem by Thompson, Barger, or Mullen.  I'm still reading through it, but heterodyning only gets one mention in the index, and it's a trivial reference that doesn't address the NAS panel's point.

Correct.

BTW, the appearance of the Decker crosstalk on channel 1 has a greater significance than one might expect. Weiss and Aschkenazy's analysis of the "GK shot" is predicated on the assumption that the impulse pattern in question is either a (synthetically-derived) gunshot or a series of random impulses (basically, noise). However, the Decker crosstalk overlies the area where the BRSA/WA "shots" are found. That changes the situation. Proper probabilistic analysis would require the Decker crosstalk be accounted for as a partial or whole source of the "shots" as well as the string-of-random-impulse hypothesis. This is true no matter the origin of  "hold everything secure" on channel one.

Yes.  Just one of the problems with the WA probability result.

Michael

[Mitch Todd]

Wow, I see why McAdams loves you as a source. Your claims are erroneous. I will simply leave it to each reader to compare your comments about Thompson's acoustics chapters with the acoustics chapters themselves. People like you will never admit that the acoustical evidence proves at least four shots were fired at JFK.

McAdams isn't the only person who likes O'Dell's work. Thompseon does too, and mentions O'Dell quite favorably. Did you not actually read the book?

[Michael T. Griffith]

McAdams isn't the only person who likes O'Dell's work. Thompseon does too, and mentions O'Dell quite favorably. Did you not actually read the book?

If you actually read the book, you'll see that Thompson commends O'Dell for his raw-data research, not for his claims about the data. Dr. Thomas has said the same thing: that O'Dell has done good raw-data work but that his claims about the data are wrong. By the way, Dr. Thomas spends several pages in Hear No Evil responding to O'Dell's claims.

Folks, go read Thompson's chapters on the acoustical evidence and also Dr. Barger's and Dr. Mullen's appendices, and then make up your own minds.

[Michael T. Griffith]

There was no expectation that they would publish Barger's letter in their report, and Barger's letter didn't contain anything that would debunk what the panel found.

Hogwash. Barger's letter, among other things, presented evidence that the Decker "hold everything" transmission had to be an artifact, not crosstalk.

And one would think that the NRC panel would have at least addressed the counter arguments that Barger presented in his letter, but they ignored them because they had no answer for them.

Quote from: Michael T. Griffith on January 30, 2021, 01:05:26 PM
I think it would be helpful to keep in mind that even the NRC panel admitted that there was only a 7% probability that the numerous locational correlations between the dictabelt gunshots and the test-firing gunshots were the result of chance (https://miketgriffith.com/files/hscaacous.pdf, pp. 12-13).

It wasn't random chance.  That doesn't mean there was gunfire.

More hogwash. I wonder if you understand what we're talking about here. The NRC panel was responding to BBN's powerful observation about the amazing locational correlations between the gunshot impulse patterns and the test-firing impulse patterns. By disputing one of the values that the BBN scientists assigned, the NRC panel reduced the probability of gunfire from over 99% to 93%.

Figure 22 in the BBN report shows the microphone positions along the motorcycle route where high correlations were obtained. The BBN scientists referred to this figure in explaining why there was less than a 1% probability that chance caused the time-distance correlations:

Even a brief glance at Fig. 22 shows that the microphone locations that correspond to correlations at the three times after the first impulse tend to progress uniformly forward along the motorcade route. This conclusion can be quantified statistically by the chi-square test. If the motorcycle were not moving through Dealey Plaza at the time of the assassination, the distance along the motorcade route would be a meaningless coordinate, and the microphone locations for the correlations that exceed the detection threshold would occur at random. When the chart in Fig. 22 is partitioned into a 2 x 2 table by separating time at 5 sec and distance at 250 ft, we find 1, 6, 8, and 0 correlations in the four sections reading from left to right, top to bottom. But the expected number of correlations to be found in these four sections, if the correlations occurred at random, are 4.2, 2.8, 4.8, 3.2. The value of chi-square for the observed and expected values is equal to 11.4. There is only 1 degree of freedom in this 2 x 2 table, and the probability that this large value of chi-square could occur at random is less than 1%. Therefore, there is little doubt that the distance coordinate is meaningful, and we conclude that the motorcycle was moving through Dealey Plaza and did, in fact, detect the sounds of gunfire. (BBN report, 8 HSCA 104)

The NRC panel made no effort to explain the significance of the fact that their own calculation found a 93% probability that the locational correlations occurred because the impulse patterns on the police tape were recorded by a motorcycle in Dealey Plaza during the assassination. In fact, they did not even specifically mention this. They simply noted that they determined the probability of chance was 7 percent and acted as though they had dealt a strong blow to the BBN report. Yes, 7% is more than "less than 1%," but it is still an extremely low probability of chance.

What makes the locational correlations especially powerful is that they show the correct pace and distance of movement that one would expect if the mic were on a motorcycle that was moving along the motorcade route.