The House Select Commitee on Assassinations concluded that John F. Kennedy was the victim of a conspiracy based on the recording of the gunshots fired in Dealey Plaza, captured over a police radio. A total of 7 impulses were caught on the tape, but citing budgetary constraints, the HSCA only had 4 of them analysed. The analysis concluded that all 4 were gunshots, two of them occurring within 1/2 a second of each other, too close to be fired by one man. Comparisons of the echoes with test shots fired in Dealey Plaza confirmed that at least one of the recorded shots had indeed been fired from the Grassy Knoll. Needless to say, the existence of 5, rather than just 3, gunshots destroyed the Oswald as lone gunman cover-up. Warren supporters quickly tried to dismiss the audio record of the gunshots by claiming that the recording was actually of gunshots in another part of the city, and confused for Dealey Plaza shots because of a timing error. Without explaining just where the other shots had occurred, or why the echo patterns matched matched the test shots fired in Dealey Plaza, the Warren supporters declared victory. New research has shown that the report that dismissed the audio recording of the gunshots was itself deeply flawed, and ignored evidence that confirmed both the location and time of the recording as being in Dealey Plaza at the time of the JFK assassination. This means that the original House Select Committee on Assassinations conclusion is the correct one. There were at least four gunshots in Dealey Plaza, two of them within 1/2 second of each other, and at least one of the shots came from the Grassy Knoll.
The machine itself and how it operated, the timing compared to the Gray recording and the speed that was not a constant and changes the location of the shots compared to Zapruder.
The fact the Dictabelt records over itself without an erase feature, so any 'old data is still layered into the tape.
The placement of the 'open mike', that put the officer in question, H.B. McLain, at 120-140 feet from the President at the first shot, but Zapruder shows him at 250 feet or more.
The Dictabelt recording attributed to McLain's open mike also records a rising and falling siren. McLain was one of the officers escorting the limo to Parkland. His siren was blaring the entire time.
The sounds on the Dictabelt cannot be resolved to the photographic evidence of Zapruder. The timing is off anywhere the 'shots' are placed in reference to where McLain was positioned and where Zapruder shows the officer.
That in itself lends to disputation of the recording.
Erroneous conclusions based on subjective data, and the Dictabelt acoustic evidence is subjective, makes every conclusion after that incorrect.