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James DiEugenio

Early study of Acoustics Evidence?

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7 hours ago, Cliff Varnell said:

What a crock!

Does the acoustics evidence prove anything we don’t know from the physical evidence found with the body, the properly prepared autopsy material, and the contemporaneous reports of witnesses in position of authority?

Why muddle the prima facie case for conspiracy with highly technical redundancies?

The hole in the shirt evidence is so convincing it should be taken to Donald Trump, have its own website and probably have a rockface carved with it.... Until then. 

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8 hours ago, Matt Allison said:

It looks like there is BBN data at Mary Ferrell, which is helpful. There is a paper by Michael O'Dell that discusses his attempt to sync the Ch 1 recording and the Ch 2 recording using Decker's "Hold everything" message while using 60 cycle hum to maintain the tape's correct speed; seems well done to me, I'd be curious if Don Thomas had a rebuttal to it or what his thoughts are.

Don Thomas does have a very good rebuttal (on MFF I think) basically it revolves around the dictabelt stylus skipping at definable points. 

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Posted (edited)

James DiEugenio posted yesterday:

"Well Chris, he seems to be still around.  GIve him a call."

Not sure which Chris this was meant for, but if it was me, please be assured that I have far better and more important things to do than chasing down this kind of rubbish, LOL. Having spoken with people in the FBI, DPD, HSCA, and Ramsey Panel who were directly involved in the whole dictabelt/acoustics issue, and highly respected researchers on both sides of the debate, I don't think I'll bother with this one, thanks!

Happy Easter to all, and stay home, stay safe, and stay well.

 

 

 

 

Edited by Chris Scally
Minor wording change/addition

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3 hours ago, Eddy Bainbridge said:

The hole in the shirt evidence is so convincing it should be taken to Donald Trump, have its own website and probably have a rockface carved with it.... Until then. 

Until then let’s take an open and shut case for conspiracy and make it a matter of highly technical dispute to employ “experts” who can bore the hell out of anyone younger than 50.

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7 hours ago, Chris Scally said:

James DiEugenio posted yesterday:

"Well Chris, he seems to be still around.  GIve him a call."

Not sure which Chris this was meant for, but if it was me, please be assured that I have far better and more important things to do than chasing down this kind of rubbish, LOL. Having spoken with people in the FBI, DPD, HSCA, and Ramsey Panel who were directly involved in the whole dictabelt/acoustics issue, and highly respected researchers on both sides of the debate, I don't think I'll bother with this one, thanks!

Happy Easter to all, and stay home, stay safe, and stay well.

 

Hi Chris, I would be very interested to have your view on the acoustic evidence. I would like to flip the commonly held view that the Z film records the assassination. If the Dictabelt records the assassination, what does that say about the Z film? 

 

 

 

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Posted (edited)

Matt, forgot to hit "quote" in responding to you.
I can't find data on the frequency range of the Harley or any bike yet other than the frequency related to rpm and decibel ratings. Sub sonic is about rate of speed relative to the speed of sound but I am concerned with the frequency of sound.  I could see the frequency of a 1200 being very low but it goes way up with other bikes like a 45 running at 2200rpm. I don't mean to confuse the frequency of the rpm with a single engine pop but it sounds like the frequency of single pops goes way up when each pop takes less time to execute. So I don't know the answer but my gut feeling is voice and engine sounds can overlap in frequency. From what I have read so far the human voice tops out around 2000hz but goes as low as 80hz.
If the dicta belt does take out engine sound I would need explain what the 2200cpm sound is since it only happens when that particular mic was keyed. And whatever it is is would have to be within the range of the human voice or higher if that is all the dicta belt can record.

Edited by Chris Bristow

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Posted (edited)

Here is 16 minutes of the Dallas tape. Whistle is at 9:40. There are many parts of the tape in which the motor sound is clearer. At 15 minutes there is a good sample and at 15:35 you hear it start to accelerate. Between 15:40 and 15:50 the engine revs a bit then takes off and the rpms go way up till 15:50 when he would shift, which is consistent with the rpm at that point. What sounds like the rpm range is definitely in line with a Harley motor. In the 45 demo I provided "motoridle" you hear the 45 accelerate away towards the end.  Compare it to the sound at 15:35 to 15:50 of the dicta belt and see what you all think.
EDIT: Oops the "motoridle" tape does not have it accelerating away. I will find it and post.

motoridle copy.wav

https://www.nap.edu/resource/JFK_audio/tr6B_128.mp3

Edited by Chris Bristow

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I'm not saying the audio analysis is useless but I have a fair amount of experience recording, mixing and engineering location audio in a variety of situations and can't wrap my head around how anyone can arrive at conclusions with what is available. Anyone in film or television production knows the audio is the thing that gets screwed up more than anything and that's when everyone's trying to do it right.

The audio in this case was chance recordings with ancient equipment and too many variables to make it any more than an entertaining discussion IMO.

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4 hours ago, Bob Ness said:

I'm not saying the audio analysis is useless but I have a fair amount of experience recording, mixing and engineering location audio in a variety of situations and can't wrap my head around how anyone can arrive at conclusions with what is available. Anyone in film or television production knows the audio is the thing that gets screwed up more than anything and that's when everyone's trying to do it right.

The audio in this case was chance recordings with ancient equipment and too many variables to make it any more than an entertaining discussion IMO.

Hi Bob, you should read the analysis before dismissing it. The dictabelt has recorded wave forms. When test shots were fired in DP and the wave forms compared, at different points on the Plaza, statistically significant matches were found.  Or put another way ; how the heck do you explain a close match between a test rifle shot and an alleged recording of the assassination?

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7 hours ago, Eddy Bainbridge said:

Hi Bob, you should read the analysis before dismissing it. The dictabelt has recorded wave forms. When test shots were fired in DP and the wave forms compared, at different points on the Plaza, statistically significant matches were found.  Or put another way ; how the heck do you explain a close match between a test rifle shot and an alleged recording of the assassination?

Fair enough but one reason I haven't looked closely at it is because I think there are more solid threads of inquiry. Even if they were perfect matches I'm not certain it would be probative because of the variables involved. It could be called another brick in the wall I suppose and I do think it has value.

 

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I found a couple new things regarding my pet theory about the 45ci engine. The dispatch supervisor had weighed in and felt the sound on the belt was definitely a three wheeler belonging to a different cop who was not in the plaza. The supervisor must have felt he could identify engine sounds on the dicta belt that match the engine sounds he heard as a dispatch supervisor.  The quote is from Wikipedia.
"Jim Bowles, a Dallas police dispatcher supervisor in November 1963, and later Dallas County Sheriff, believes it originated from a particular officer on a three-wheeled motorcycle stationed at the Trade Mart."  I said in a previous post that the dispatchers opinion would be a highly qualified source to weigh in on engine sounds. So I find it persuasive.
In the interview below Mclain said Bowles sat him down to listen to the tape and they agreed it was the 3 wheeler.   Mclain explains the 45ci sound and names the 3 wheeler officer as Les somebody(Can't make out the name). It is in this 6th floor interview and he talks about it starting at 30:00min. Mclain also says at the end that he does not believe JFK was shot from the TSBD.
https://www.youtube.com/watch?v=-FNK2oS491M

 One of the the acoustic experts testimony at the HSCA, Dr Barger, pointed out that Mclain's testified that he stopped as they turned onto Elm because the motorcade had bunched up. Dr Barger said this was consistent with the sound on the tape because you could hear Mclain slowing way down just prior to the first shot. The engine is the only sound I can think of that would indicate slowing down. What sounds to me like a 45ci does exactly that. It slows to near an idle just before the theorized moment of the 1st shot.
 Dr Barger and Mr Bowles are both claiming to be able to identify the engine sounds on the tape. One is an acoustics expert and the other highly experienced at hearing the sound of an engine that comes over the Dallas Police radio.
There is not any question as to whether you can hear engine sounds over a radio. The question is can a dicta belt record that engine sound. I would have to say a dispatcher identifying the dicta belt sound as replicating the sound he would intimately know to be the specific difference between a 1200cc and a 45ci Harley, is very strong evidence that the dicta belt did record the engine sounds.

 

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