gedlee said:
No, its not a "hypothesis" - its plain physics (science is happening "here and now" – remember?)
And also no – not my part actually, to verify audibility – before I state the obvious - an other white area on the map of psycho acoustics
And yes – everybody is invited to watch out for correlating his subjective experiences / perception with the above
Michael
Earl, if you tell me that *you* can't hear what I was presenting – I am fine with that.
It simply means *my* ear brain system is tuned "different" from yours.
On the other hand I invite everybody (you included, Earl) to discuss the topic I brought up.
I'm actually not interested what a somebody writes in *any* paper, telling me what I *can't* hear / detect. – and again Earl - I am asking you to drop that DampfWalzen habit.
Truth is subjective – depending on perception (remember?)
I always found that tweeters without rear chamber didn't sound right to me.
I am not claiming to be as experienced on compression drivers then many others here but to the ones I have been "in depth" working with - the same specific quality applies.
What I experience with my completely front / back symmetrically AMT right now is the *complete* absence of that sonic pattern when operating with the back open.
The physics presented above don't "tell the whole story" for sure, but give me a comfortable handle on the subject.
And besides that, anybody who wants to claim different glues on the VC / different surrounding materials / different absolute phase / different .... may be easier "detectable" than what with ease can be calculated ?
Michael
It simply means *my* ear brain system is tuned "different" from yours.
On the other hand I invite everybody (you included, Earl) to discuss the topic I brought up.
I'm actually not interested what a somebody writes in *any* paper, telling me what I *can't* hear / detect. – and again Earl - I am asking you to drop that DampfWalzen habit.
Truth is subjective – depending on perception (remember?)
I always found that tweeters without rear chamber didn't sound right to me.
I am not claiming to be as experienced on compression drivers then many others here but to the ones I have been "in depth" working with - the same specific quality applies.
What I experience with my completely front / back symmetrically AMT right now is the *complete* absence of that sonic pattern when operating with the back open.
The physics presented above don't "tell the whole story" for sure, but give me a comfortable handle on the subject.
And besides that, anybody who wants to claim different glues on the VC / different surrounding materials / different absolute phase / different .... may be easier "detectable" than what with ease can be calculated ?
Michael
Truth is subjective? I don't understand this. For example: "The earth orbits the sun not the other way around." What possible subjective opinion could one have about this truth?
I'm not going to take what one person tells me I can and can not hear as the truth either but Earl is referring to a controlled scientific experiment with many listeners. If you read the paper and have concerns about how the experiment was conducted or disagree with the interpretation of the data it generated that's one thing, but to dismiss it as meaningless because it's "in any paper" seems unreasonable. Where would we be with attitudes like that? You certainly wouldn't be typing messages on a computer about speaker design. A lot of very non-subjective truths were discovered to make that clip along at over a million operations per second.
I'm not going to take what one person tells me I can and can not hear as the truth either but Earl is referring to a controlled scientific experiment with many listeners. If you read the paper and have concerns about how the experiment was conducted or disagree with the interpretation of the data it generated that's one thing, but to dismiss it as meaningless because it's "in any paper" seems unreasonable. Where would we be with attitudes like that? You certainly wouldn't be typing messages on a computer about speaker design. A lot of very non-subjective truths were discovered to make that clip along at over a million operations per second.
poptart said:
OT excursion:
Are you sure about that? - I'm not referring to historic development of perception of "truth" on that topic though
Consider the following:
Take the earth and the sun - and take away all the rest of the planets / suns / moons / .. in universe.
Leave sun and earth to be the only masses left in universe - and now tell me - which is orbiting which ?
Michael
Obviously I am a computer programmer not a philosopher, I like my truth to come in 1 or 0.
Re-imagining the universe or simply staring at the television and stating that it's off when everyone can clearly see it's on isn't going to help us build better speakers though. I do believe the universe exists independent of my own existence and that there are then truths that exist independent of my perceptions or beliefs about them. I can't imagine living my life believing that things existed simply because I decided they did. As I said I'm not a philosopher so I honestly don't know, what happens to morality when you decided all truth is up to you? Or what about a much simpler case, 1+1=2? Or 1 volt across 1 ohm will draw one amp? We would be paralyzed as speaker builders if we did not accept these things as truth.
Re-imagining the universe or simply staring at the television and stating that it's off when everyone can clearly see it's on isn't going to help us build better speakers though. I do believe the universe exists independent of my own existence and that there are then truths that exist independent of my perceptions or beliefs about them. I can't imagine living my life believing that things existed simply because I decided they did. As I said I'm not a philosopher so I honestly don't know, what happens to morality when you decided all truth is up to you? Or what about a much simpler case, 1+1=2? Or 1 volt across 1 ohm will draw one amp? We would be paralyzed as speaker builders if we did not accept these things as truth.
mige0 said:
Those were interesting simulations Michael. The problem I have is that if I set up an experiment to verify your idea I don't measure anything that looks like that. I think to show what is happening it is necessary to use realistic approximations. Make some measurements and look for HD and IM side bands. These things need to be quantified.
john k... said:
Thanks, John.
I certainly will do some measurements – as time allows.
It should be possible to measure the effect in the time domain as well - maybe even more easily.
As this behaviour is strongly repetitive, we should be able to get significant results with averaging if the frequencies involved are set properly – what you think?
Michael
poptart said:
Yes, "truth" can be subjective when the subjects of a study/experiment have all been raised in a culture based on "western music". It does not address the possibility that subjects from other cultures may have responded differently. This shouldn't be confused with the examples that you gave, which are from the hard sciences.
For electrical signals, that's how it's going to look. The problem with acoustic signals is that you can only measure somthing similar when both signals are same ideal wave source. Not many drivers can do that, and you have to pic the right frequencies such that the wave front is the same shape so that it's not dependent on mic location.john k... said:
mige0 said:
I don't think that I'm the one being closed minded and obnoxious here!
The data is clear and it wasn't just one person, but about 30 who failed to detect any nonlinearity in a compression driver and some of those were audio engineers. Just because the data is not to your likeing is no reason to reject it and "kill the messanger".
When you have contrary data done in a comparable way then I'd love to see it, but for now rejecting all the data that there is simply because it doesn't fit your position is hardly scientific. Why do scienec at all if thats the way you are going to deal with it?
john k... said:
John, the software used here is LT-SPICE / swCAD-III.
I could have used another simu software like ORCAD as well, but LT-SPICE is way good enough for that (and much more) *and* available from LT technologies as freeware.
So everybody easily can verify my simulation.
http://www.linear.com/designtools/software/switchercad.jsp
There are three voltage sources – seen on the pix from left to the right :
V2 is a simple sine set to 2kHz at 1V:
An externally hosted image should be here but it was not working when we last tested it.
V1 is a so called "Time-dependent single frequency FM voltage" (syntax outlined in the help menu under "voltage sources") – nothing else than a FM modulated sine voltage source - set to 2kHz at 1V with a modulation at 100Hz :
An externally hosted image should be here but it was not working when we last tested it.
V7 is same as V1 – set to be of opposite phase and frequency modulation to mimic the mirrored signal :
An externally hosted image should be here but it was not working when we last tested it.
T1 is a delay line set to 4us to mimic the late arrival of the mirrored signal :
An externally hosted image should be here but it was not working when we last tested it.
Well and last but not least – the transient command is set to calculate in the time domain at the time frame displayed, rather than in the more usual frequency domain :
An externally hosted image should be here but it was not working when we last tested it.
Thats it
(half an hour to line up the simu / two more hours to set up everything else to have the posting ready).
John, if you like to have the file for a *very* quick start up - I'll email it to you if you send me a PM
Michael
gedlee said:
You may have noticed that I don't do what I do for the sake of science but rather to get clarification about what *I'm* interested in (and maybe open a door for others as well *if* we are lucky).
As a side note :
remember that "science" was kind of invented by the clergy to support *their* point of view – way back in dark times of inquisition and before – and sometimes there still is a facet in "science" that reflects that "axiom and belief thing" - not saying "science" hasn't developed, mind you.
Michael
mige0 said:
Adopted by some clergy, yes. Invented? Hardly. Regardless, it's immaterial. Science is not a thing or a collection of things (or facts). It's a process by which we can uncover the underlying rules that govern the physical relationships between things. The only article of faith that the process requires, as far as I can see, is that the physical rules of the universe we study are not whimsical. We expect them to be the same tomorrow as they were yesterday and today, though our knowledge of them will change.
Sheldon
Speaking of Cosmology, we also assume that the laws are independent of location and many physicists agree that there is no reason to make this assumption. But the fact is that all data points to the laws being universal with no variation in time or space.
Are you guys aware that the latest thinking in cosmology is that the univese is digital? Yep, they now believe that time and space are not continous but are in fact discrete. How cool is that? Now we only need to sample at the "universal sample rate" - a Plank-time - and no one could ever argue that we aren't sampling high enough
Are you guys aware that the latest thinking in cosmology is that the univese is digital? Yep, they now believe that time and space are not continous but are in fact discrete. How cool is that? Now we only need to sample at the "universal sample rate" - a Plank-time - and no one could ever argue that we aren't sampling high enough
gedlee said:
Are you guys aware that the latest thinking in cosmology is that the univese is digital? Yep, they now believe that time and space are not continous but are in fact discrete. How cool is that? Now we only need to sample at the "universal sample rate" - a Plank-time - and no one could ever argue that we aren't sampling high enough
Lets hope they use a jitter free clock for our universe
gedlee said:
*You* know ?!?
mige0 said:
Lets hope they use a jitter free clock for that
There is actually a hypothesis that the clocks of each particle do have jitter or at least do not have the same time reference for zero. This would exaplain why we have to view all interactions between particles as random events, because the clocks are not synchronous. But a particle can react with itself in perfect synchronization and as such acts like a wave. In other words, the clock jitter would explain the particle/wave duality and the need for probabilities in Quantum Mechanics that has troubled so many physicists for so long.
