True.... that's why they don't shut down the avionics in the aircraft. They shut down the engines but not the avionics nor the cabin systems.
In the late 80s our flight in Honolulu got delayed for half an hour at the gate after we had boarded. The aircraft was on its own power so the pilots cut back on the AC after we had boarded.. a full cabin... 90F and humid outside. After about 15 minutes we almost had a mutiny on board so the pilots had to burn some fuel.
The whole point of adding GPS is to help in "bounding" the navigational solution ( longitude, latitude and elevation ) so the inertial units can converge faster. They are required for "navigational aids" in commercial air spaces. Military attack aircraft can ignore it, but the cargo buses can't. No way will the EU allow a C17 or C5 over its skies unless they can fly safely amongst their civilian airliners.
Even so, we did fly over LAX several times with our civilian TCAS taken over by our prototype FFS.. Nothing like six people in the cockpit with binoculars looking out for traffic, 20,000 feet directly over the runways. Yikes! I gotta admit I was impressed by the keen eyesight of those pilots.
The best was touch and go in formation at Palmdale while those FedEx pilots in a couple of heavies kept complaining and bitching that they got waved off by those big grey planes breaking all the rules. He, he, he....
DIY flying, for sure... and wearing Bose headsets, no less. I guess that explains it, huh? The Bose... formation nowhere.
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Sure. It's also the RVSM requirements. Some are excempt from those
https://www.faa.gov/air_traffic/publications/atpubs/foa_html/chap6_section_9.html
George
1. Despite many stating that there is no such thing as reflections of audio frequencies on short cable lines, it was measured years ago by Cyril Batemen, written up, with details on building a test setup (reflection bridge) to allow others to duplicate the results.
2. George (gpapag) built 3 variations of the bridge and duplicated Cyril's results.
3. Hans designed some cables using lumped elements to simulate cables with impedances consistent with the load, and reported hearing a difference in sound.
These results alone prove that consideration of a speaker cable as a t-line is a valid thing to do. I've been saying that since 2012 IIRC, from my work starting back in '81. And yesterday proposed to higher ups at work this T-line application in order to get rid of latency issues we have on high bandwidth (1Khz) feedback positioning systems. It was well received of course, because if I can replace 100 feet of twisted pair with 100 feet of triaxial cable to lose 40 uSec of (measured) latency, it will be adopted around our entire machine in 180 locations, and the concept will be used on further generation synchrotron machines. (note, the shield to shield impedance, while not specified in the Belden cut sheets, is roughly 10 ohms based on dielectric and physical dimensions.)edit: also note that moving the electronics to the magnets is not an option both due to radiation and space constraints.
4. Pano varied the line impedance and again reported a difference in sound.
Edit: I have always recommended using a cable impedance of roughly 25 ohms as it is easy to get there, and really drops latency/phase shift vs frequency variance. going much lower gets into diminishing returns area.
As a group, the members of this forum are indeed advancing what we know.
While there are some here who post in a seemingly arrogant manner arguing against these advanced concepts, I am glad they do that. It helps to keep the arguments better grounded in reality, and forces us all to consider every aspect...a self check as it were.
John
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This thread wasn't started to prove audibility. It was started to measure something. And things HAVE been meausured. Makes it a very successful thread.
I would ask that you please read my posts very carefully so that you do not attribute erroneous statements to me. You have done this in the past, but I would appreciate you discontinuing that practice in the future.
I did not say audibility was proven, as you just attributed to me. I said:
"3. Hans designed some cables using lumped elements to simulate cables with impedances consistent with the load, and reported hearing a difference in sound. "
And I also said:
"4. Pano varied the line impedance and again reported a difference in sound."
Reporting a perceived difference is not proof.
Edit: Which is why I designed a test methodology (over a decade ago) specifically created to perceive any cable induced changes, a test one can easily perform at home. And it eliminates amplifier design/interaction as well, lest a cable cause a response change in the amplifier. Control of confounders is very critical here.
John
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@billshurv That's correct, almost all of us know rules of propagation of signal through the cable. I would still assume to talk about important things for audio, as this is the audio forum. Contrary to many others I do not think that the BT threads have had much merit in audio other than a tech - talk on everything.
What I find amazing is that the ASR group, "we measure, we don't have to listen", only believes in its own measurements. They reject any other kind of measurements.
Classic Greek Science.
The belief that rationalism trumps empiricism.
The ASR crowd believes only in their own dogma and their own measurement set.... anything outside of that realm is ridiculed.
Just like the Classic Green Philosophers - who rejected the '0' as being irrational to their sensitivites.
You what's really funny?
Watching a B1 over the desert at 400 feet doing 1000 mph.
Or a set of C17s, in formation flying at 2000 feet above the ground....
...or 1000 feet over the ocean, making a 180 deg turn using a hapless fishing boat as a pylon (*)...
...or buzzing the rich people's homes on the hills around the approaches to Spokane, to the point we could tell it was a new Ford pickup, not a Chevy.
Then you realize that the civilian standards are incredibly tight. They leave a lot of room to maneuver... a lot of room. But then, the seatbelts in an AF plane are a four point harness... which they should have in a civilian plane as well.
I mean, even civilian airliners have a performance envelope that is seldom approached... so those pilots get lulled by a lack of "action" and will make mistakes that drop the plane out of the sky.
(*) He just happened to be there, at the limit of our programmed east leg... That guy likely went back to shore and told the story about those grey ghosts coming out of a grey sky (visibility of less than 3000 feet) and they all thought he was on peyote or something...
I do not think you can simplify like this. Who is "ASR group"? Is it some unified set of people with same opinion? I do not think so, it is same as everywhere. Here, there, and everywhere - you know 😉.
If you think someone's reasoning is wrong, then come with yours. However, it should always be based on something. And how do you know that some people listen or not? They only listen if they shout it from the rooftops? I do not think so.
@PMA, IIRC you mentioned before having professional classical music friend whom you said could hear some things that you couldn't. Again IIRC, you later said you had learned how to pass an ABX test, and you found it required sustained concentration.
If I misremembered any of that please do correct me.
If I misremembered any of that please do correct me.
The "ASR Group" is the nomenclature that I use to define that group of people who believe that we know everything there is to know. about audio. They are rationalists.
In science, and real life, there are fundamentally two types of people:
The rationalists: They believe that the world is as we think it is and dismiss any thought and experience that contradicts their beliefs. This group constructs interpretations of the World based upon how they think it SHOULD be based entirely about their logical thinking.
The empiricists: They believe that the world IS as it IS and that we must change our interpretation of the world whenever we are faced with thoughts and experiences that contradict out interpretation. This group constructs models of the world based upon how they think it COULD be based upon their interpretations.
Hence, "Classical Greet Scientists" were rationalists and Modern Western Scientists (*) are empiricists.
Note the interesting part here... it is possible for rationalists to cloak their school of thought in the wrappings of the other... hence ASR, Julian Hirsch, Global Warming, Fauci, etc... they use SOME of the tools of the empiricists at face value but then they apply their dogma to twist the data to "prove" their a priori "discoveries".
Conversely, it is also possible for people who do not use formal scientific models to discover facts and experiences that contradict the established empirical models... in the audio world this would be like Enid Lumley, Harry Pearson, J. Gordon Holt... etc... these people use their own 'natural' means of measuring (they listen with some measure of rigor). Normally their discoveries will eventually grow into the body of empirical science by modifying the models and creating appropriate measurements: Intermodulation Distortion, Phase Shifts, Impedance Matching... etc...
I have come up often to defend the empiricists, because I am one. I believe that we operate with models that reflect our current thought of how the world is, but are by no means the correct interpretation of nature, just a working hypothesis. I also believe that our models become invalid with a single contradicting experience.
I was BANNED from the reddit "audiophile" (**) forum because I pointed this same thing, but the moderator, who, I found out, is active in ASR, felt that I was making people uncomfortable, challenging their comfortable thoughts. Essentially, faced with a different reality, the ASR group will shut you down, will NOT want to hear you.
BTW: Notice that I have also read Wittgenstein and Kuhn. They are eye openers for any one who is interested in empirical science.
(*) Not to be confused with Political 'Scientists'.
(**) A joke group, actually.... current taken over by people who are ASR acolytes or newbies who are into buying Superscope and Radio Shack receivers at inflated prices... nothing about audiophiles in there..
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Not 5 point? Seems odd for something that can fire the seat out on a rocket(or the whole cockpit if you are showing off).
Of course. My point is that we can also talk about things that are measurable without proving if they are audible (as proof is a difficult thing when humans are involved). More valid than another discussion on capacitor rolling!
Did they ever? All the fun happens on these sort of threads.
Airliners and cargo busses don't have ejection seats.
It be somewhat unnerving flying in a JAL Heavy over the Pacific at 40K feet and noticing that your pilots had ejected from the cockpit.... WTH?
Maybe they confused the ejection buttons with the power reset in their Bose Acoustimass headsets?
Not trying to go after you. A lot of what you say makes sense. But I have some problems with some of it as follows:
There are probably better and more modern authors besides those philosophers to read. Why 'better?' Lets see what you think:
First, regarding the idealized philosophical views referenced above, what about this dichotomous issue: https://quoteinvestigator.com/2014/02/07/two-classes/
Aren't people more correctly described as being in statistical groups that to some extent overlap, as opposed to being distinct?
Moving along then: Without saying more about your above referenced readings and their implications, have you also read more recent scientific finding and opinion?
Some examples:
https://www.betteryou.ai/what-you-s...~:text=“What you see is all,what we don't see.
Or how about: https://www.goodreads.com/author/quotes/55727.Jonathan_Haidt
Or perhaps: https://www.apa.org/monitor/2012/02...ays.&text=Comment:,marvel, but a fallible one.
There is a lot more of science beyond philosophy. Yet, there is a philosophy of science:
https://en.wikipedia.org/wiki/Philosophy_of_science
Some of the guys at ASR may not have been exposed to or may not be willing to accept the philosophy of science. Is that more to your concern?
As a physicist I always remember the words of my advisor:
"Tony, perhaps someday someone may come up with a theory that everything is run by little green men from Mars... and if this theory matches our measurements and correctly predicts new ones we will have to accept it!"
I live by those words from Dr. Brown.
Approach things with an open mind... the ASR group has a closed mind.
That is my concern.. .and I will not accept people with closed minds telling me what to do or what to think.
Not surprisingly that goes beyond audio, huh?
Thanks, btw, for the other links... yep Wittgenstein and Kuhn are indeed seminal in the field. And always remember that until the 19th century, Physics was known as Natural Philosophy.... and that it was Leibniz, not Newton, that invented The Calculus. ;-)
And, to me, Physics IS Science... Mathematics is sheer, but useful, lunacy and everything else was Physics at one point. Only Geophysics is fun, mostly because they drink as much beer as physicists...
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