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Storm
SFN Regular
USA
708 Posts |
Posted - 07/04/2005 : 09:24:47
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Last week my family and I visited Mt Zion Cemetery in Dade City Florida...Spooky place.. This is the audio we discussed in chat...the thump eminates from the speakers but yet the truck is not on...not only is it not on ...it will not start..yet the sound eminates methodically..never changing... had much difficulty trying to upload..but finally we got it to work thru this...
http://www.geocities.com/paranormalmoon/index.html
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Kil
Evil Skeptic
USA
13477 Posts |
Posted - 07/04/2005 : 11:08:21 [Permalink]
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I can't seem to get the sound file to work... |
Uncertainty may make you uncomfortable. Certainty makes you ridiculous.
Why not question something for a change?
Genetic Literacy Project |
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Ricky
SFN Die Hard
USA
4907 Posts |
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Kil
Evil Skeptic
USA
13477 Posts |
Posted - 07/04/2005 : 11:49:20 [Permalink]
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quote: Ricky: It's cause you use a Mac.
Bite me. |
Uncertainty may make you uncomfortable. Certainty makes you ridiculous.
Why not question something for a change?
Genetic Literacy Project |
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Ricky
SFN Die Hard
USA
4907 Posts |
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Kil
Evil Skeptic
USA
13477 Posts |
Posted - 07/04/2005 : 12:10:11 [Permalink]
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quote: Ricky: But did my fix work on your computer as well?
No. Is there a way to convert it to quicktime? Or just about anything else? |
Uncertainty may make you uncomfortable. Certainty makes you ridiculous.
Why not question something for a change?
Genetic Literacy Project |
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Kil
Evil Skeptic
USA
13477 Posts |
Posted - 07/04/2005 : 12:13:16 [Permalink]
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quote: Ricky: And I'm sorry for all the times I'm going to do it in the future too.
PC users have settled for quantity over quality. So, whatever... |
Uncertainty may make you uncomfortable. Certainty makes you ridiculous.
Why not question something for a change?
Genetic Literacy Project |
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Ricky
SFN Die Hard
USA
4907 Posts |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 07/04/2005 : 14:53:46 [Permalink]
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If you DL the file, try opening quicktime, and then opening the file using quicktime.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong. -- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n. The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 07/04/2005 : 14:56:53 [Permalink]
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quote: "Is there anybody trying to communicate with us?"
Yes. To bad you are paying more attention to a wierd clicking noise in your speakers than you are to the people trying to communicate with you.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong. -- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n. The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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ktesibios
SFN Regular
USA
505 Posts |
Posted - 07/04/2005 : 15:12:53 [Permalink]
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Ricky's fix worked for me, but I'm a PC user. Once I had the file saved on my computer, I decided to take a look at it with my home audio editing tool, Cool Edit.
First, I measured the intervals between pops, using the tip of the first positive-going peak in each pop as the reference points. For ten intervals, every single measurement came out to 1.409 seconds.
The readout resolution for Cool Edit is 1 ms. The ultimate limit on time resolution is imposed by the 8 kHz sample rate of the recording at 0.125 ms.
So, the repetition rate of the pops is constant at 1.409 s +- 1.125ms. That consistency suggests a natural phenomenon- one where the repetition rate is determined by physical constants, rather than a consciousness.
The amplitudes are also rather consistent. The range of peak amplitudes (again for the first positive-going peak, which was the greatest excursion for all of the pops) was from 2816 to 3840 quantization intervals. Out of 12 pops, 6 had an amplitude of 3328, 3 an amplitude of 3584 and one each at 2816, 3072 and 3840.
That's after Cool Edit, in opening the 8-bit file, interpolated it to 16-bit resolution. Gong back to the original 8-bit quantization, all of these samples would be encoded by the range x0b to x0f, which is 4 lsb wide. A +- 1 lsb bobble is expected of any A/D converter, so we have a probable range of variation of +-1 lsb, which at these peak levels amounts to a variation of approximately +- 0.8 dB. Even if we assume that the entire range of observed variation is genuine variation in signal amplitude and not encoding artifacts, the range of amplitude variation is only +- 1.35 dB.
The waveforms of the pops are very consistent. Each one is a rapidly decaying basically sinusoidal oscillation which is pretty well damped out after 2 1/2 cycles. They look like the impulse response of a system with a well-damped resonance somewhere in the 250-280 Hz area. They also look a great deal like the waveforms observed when using a "phase popper" (an impulse generator) and a microphone to check the absolute polarity of a speaker.
The spectra of the pops are also quite consistent, showing a broad peak centered in the 250-280 Hz range.
That degree of regularity, in timing, amplitude, and time and frequency domain views very, very strongly suggests a mechanistic explanation.
Based on the information available and my own experience with the technical aspects of audio equipment, the first working hypothesis I would propose would be "the amp's going tic, tic, tic because it's trying to run from a badly-drained vehicle battery". I've observed similarly rhythmic burping in devices which were connected to excessively low power-source voltages; depending on the design of the sound system there are several mechanisms which could produce this behavior.
Before I considered any paranormal explanations, I would want to test this hypothesis by investigating the sound system's behavior under conditions of low power-source voltage and high power-source impedance such as are found in run-down batteries. If possible, I would also have wanted to measure the battery voltage and check for fluctuations corresponding with the pops at the scene.
Was any meaningful, i.e., technically knowledgeable, attempt made to rule out the hypothesis that the pops were the result of misbehaving electronics? Or was "this must be something paranormal" the first and only hypothesis considered?
If the speakers were to rap out something like "shave and a haircut- two bits" in response to a queation, then I might consider putting "paranormal" on the short list of workable hypotheses. But this is just too consistent with ordinary electronic phenomena to allow naturalistic explanations to be rejected out of hand. |
"The Republican agenda is to turn the United States into a third-world shithole." -P.Z.Myers |
Edited by - ktesibios on 07/04/2005 15:16:21 |
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Ricky
SFN Die Hard
USA
4907 Posts |
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woolytoad
Skeptic Friend
313 Posts |
Posted - 07/04/2005 : 18:25:16 [Permalink]
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quote: Originally posted by Ricky
quote: Originally posted by Kil
I can't seem to get the sound file to work...
It's cause you use a Mac.
For everyone else, go to this link and download the file. Then rename it SaraStoneAudio.wav. It works in winamp.
Yeah. Mac's won't play any sort of rubbish. They are as cultured as their users
But, really. Worked fine for me. Just stick a .wav extension to the end of the file. I don't get it either. Some thumping? So what? Could have easily been the result of improperly set up equipment.
quote: My speakers, when the power cord is plugged in but the cord which goes to my laptop is out, will pick up radio channels and play them, even though they are only speakers.
Nah, that's not weird at all. Have you ever seen those crystal radio sets? All you need to pick up radio is basically a filter and simple speakers. It's quite conceivable that speakers will have some sort of circuit to filter the incoming signal. Perhaps to clean it up a bit if it picks up any noise. |
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tw101356
Skeptic Friend
USA
333 Posts |
Posted - 07/04/2005 : 18:41:41 [Permalink]
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Could the pops be a capacitor in the circuit building up a charge and discharging?
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- TW
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woolytoad
Skeptic Friend
313 Posts |
Posted - 07/04/2005 : 19:00:07 [Permalink]
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I doubt it's a capacitor. The frequency seems too slow to me. Most caps aren't large and would charge up faster than that. |
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ktesibios
SFN Regular
USA
505 Posts |
Posted - 07/04/2005 : 20:35:41 [Permalink]
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As for the cause, there are several possibilities.
Many autosound amps use a switching power supply to provide rail voltages higher than the 12VDC available directly from the vehicle's electrical system. The rail voltages set a limit on the maximum output voltage swing of the amp- with a single-ended 12V rail you can't possibly have a greater peak swing than 6V in either direction. If you use a bridge output stage you can get 12V peak, or 24V peak-to-peak. That corresponds to an 18W maximum output with 4 ohm speakers. Higher output powers demand higher rail voltages.
What we're seeing there could be a switching power supply repetitively trying to start up on an insufficient input voltage. If the vehicle's battery exhibits an excessive source impedance due to being mostly discharged, the input voltage could be high enough to permit the power supply to start up, but then collapse when the amp starts drawing current, then recover as the load abates, and so on and so on...
Another possibility is the way in which the amp's turn-on transient suppression and/or output protection circuitry works. Some amp designs don't bias the output stage on until after a delay, in which case the amp doesn't draw its full quiescent current until the output stage is biased on. In that case, we might be seeing the supply voltage collapsing under load, causing the delay circuit to retrigger, supply voltage recovering in the absence of load, and the whole cycle repeating.
Output protection circuitry could also be involved. Most amplifiers nowadays have circuitry to detect the presence of excessive DC offset at the output and either disconnect the speakers by means of a relay or shut down the output stage or power supply. Insufficient internal rail voltages can cause an output offset to develop, in which case we could be seeing a protection circuit detecting the offset, kicking the amp off, and then repeating the whole cycle each time the caps in the offset detect circuit (which usually uses a 1 Hz or so low-pass filter to differentiate between normal audio and DC at the output) discharge, or the filter caps in the power supply discharge. A Carver PM 1.5 or PM1200 power amp will behave in exactly this way if an output offset develops- the protection circuitry will shut down the power supply, a timing cap in the protection circuit will discharge, the power supply will come on again, and so forth- producing a popping noise in the speakers every few seconds.
That's all speculation- without knowing the internal details of the amp involved I can't properly form or sort out a hypothesis. As I said earlier, I'd also have wanted to know what was going on on the vehicle's power rail while the popping noise was heard.
The remarkable regularity of the noises strongly suggests an electronic cause rather than a consciousness at work. I've electronically timed drummers and I have yet to find one who can play with 1 millisecond consistency- the timing variation of a good drummer usually runs nearly an order of magnitude greater. The consistency of amplitude, waveform and spectral content all add to the inference of a electronic cause.
That hypothesis should have been the first one to be tested- preferably at the scene, but since most people don't have electronic test equipment in their cars, a second-best method would have been to check out how the sound system behaves with a power source which simulates a badly-drained battery.
Obviously, this was not done. So what we have here is a low-resolution sound file containing a phenomenon which to an experienced audio techie powerfully suggests "it's the @#$%^&* amp acting up!", insufficient information to ever propose a specific explanation strongly supported by evidence- basically a total wash, as far as drawing a conclusion is concerned.
Evidence of a paranormal phenomenon? Hardly. In fact, it's really not evidence of anything at all save Storm's lack of informed curiosity- and a sadly missed opportunity. |
"The Republican agenda is to turn the United States into a third-world shithole." -P.Z.Myers |
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