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In Reply to: No… posted by David Aiken on November 13, 2002 at 12:00:51:
It would be interesting to find that the ultrasonic signals coupled into the EEG and/or PET system, giving false results. I've seen worse.It'll also be interesting to see the peer review/reproducibility on that one.
Follow Ups:
have an effect the PET system. It is just a fancy geiger counter :-) I do not know about the EEG, that is way outside of my field of expertise,I think both could be easyly verified by taking measurements without the subjects present and with and without US fields.
BTW i like this study because it does not rely on what the subjects percieve, but rather on what stimuli their brain reacts to.
Pet is "Positron Emmision Tomography. But it has a 2mm accuracy, as that is the average distance a gamma ray travels before impact and emission of positron; giving a rather fuzzy picture of brain activity with respect to tagged molecules. Or is it the other way around... So confusing..Now, EEG, "electro"... there's a measurement that an EE can handle...
Actually, they do PET stuff here. I give tours to the college students and professors occasionally, and sometimes I actually learn about it.
But, what scares me is the fact that the medical people who do the research have no idea how the systems interact, and sometimes that can bias the results.
John,I do medical imaging software for living, so PET is one of the areas that i had to struggle with for a number of years :-). In any case the verification of the measurement accuracy is quite simple, as i mentioned in the previous post. Whether they actually calibrated their measurement is not clear from the article, i hope they did. (Nobody wants to be in the cold fusion vs. red cooler discussion.) I would love to see independent verification of their results since they do go against the grain of conventional wisdom. Better way of measuring this would be using functional MR (Magentic Resonance). The effect of HF sound field on the pick up coils would need to be studied more carefully, i suspect an open MR would be more susceptible to interference. I do not see how you could do this with a traditional small bore MR.
This one intrigues me because it could account for part of the difference between CD and vinyl.I run a CD only rig these days and have for over 10 years now, and I don't think CD sounds as bad as its worst detractors claim. I haven't had a chance to do an AB of the same music on CD and vinyl with a good rig and I rarely get a chance to listen to vinyl these days and I'm intrigued, especially since I had something like a minor stroke in 1983 and ended up with some minor sensory deficits which don't include any hearing issues, at least on normal hearing tests. CAT and MRI scans don't show anything but the sort of problems I have could occur with damage too small to show, and the view is that the damage is in the left thalamus which is one of the areas implicated for response to frequencies above 20 kHz in this study.
I wonder what a PET scan of my brain would show, but I don't know anyone who could do one and the cost for getting that done as a matter of interest rather than medical need (health insurance wouldn't cover it) is more than I'd want to spend for the sheer interest of finding out. On the other hand, if someone wants to run a study to try and replicate the results and they want to run it in Brisbane in Australia, and they're looking for subjects, I am available.
I once ran a comparison between CD and vinyl. Same song.Vinyl disappointed me. For one reason. On one song, there was ONE bass note missing from the vinyl. Only one!!!! Lowest one in the song, only used once by bass guitarist. Apparently they (recording studio) decreed that the groove excursion was high enough, and removed it!!! And to top it off, my vinyl was a 12 inch single. Only one song, 6 minutes, on one side. Modulated all to "heck".
I miss vinyl..and tubes. and klipsh horns. Oh well.
Oh yes, my system at the time was not really a sit down and listen system, just a bass KICK A## (1200 watts) system. So, any realism in the reproduction just weren't happening.
If you've played with tubes and vinyl then you're one of us. Klipsh might be a little "iffy", but, hell, they've got horns so I guess that's close enough.Anyone who would put 1200 watts to driving a pair of Kliphs is certainly crazy enough to qualify as a true audiophile.
Gave them up, though. For mobile use, they were too cranky with respect to placement, and too heavy. But boy, the sound....
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