No. At very small signal levels, cone excursion would be small, little jitter. But as excursion increases, distance to ear for higher freq content changes. At a foot per millisecond, 12 mils (.012 inch), represents 1 uSec. 1/4 inch excursion peak to peak represents 20 uSec jitter.
The program source cannot take that into account.
Jn
No, but that is another consideration. Doppler is velocity dependent, what I speak of is position dependent.
Unfortunately, it is pretty difficult to measure each independently. I imagine a test tone that could position the driver with square wave positioning could be used to see position dependency, and perhaps an other signal to create a constant velocity sawtooth, with appropriate gating of the measured signal.
But I'm not sure if those techniques have ever been tried. I recall reading that someone did Doppler measure with bass sine plus hf, just do not recall who.
Jn
Could just dial it for live levels like I do......small excursion is insignificant, leave that for the women and children (no offense to women and children intended)
IMO it is doppler, for sure. It is simply causing frequency modulation , expressed with other words as jitter(and intermodulation caused by speaker unlinearity) for higher frequency content. But this has nothing to do with ITD. At small cone excursion (caused by low frequency signal) is modulation lower..
Try Your experiment with cone moved from zero position using superposed DC, causing the same excursion as low frequency signal used before. Or use very low frequency, e.g. 1- 5Hz as "carrier"..Cone position changes will be the same as before, but now inaudible.
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Swapped out the Cardas 101 for the no name (basically extension cord) both are 14ga and both about the same strand count, plain copper.
What I can say is I know why I swapped it out in the first place.....top end glare came back. But it did speed up the perception and to tell the truth I’m not real sure I don’t like it a bit slow.....just maybe not as slow as the 101.
I really do believe this amp is designed with a slew rate that’s on the lower end of the spectrum and the 101 just enhances that.
So given I have no way to measure LCR of wire I have to go by manufacturer spec......at least I have a baseline of what ‘too much’ capacitance is.
Just have to research some more......open to suggestion if someone has a decent bulk wire (that would be applicable) in mind? Under $5 a ft ( I draw the line there!)
It’s hard asking for help with something most people find ridiculous ......but ridiculous is my reality!
Messing with publication dates happens from time to time (i fear that i´m somehow prone to aging effects)
But in the earliest post afair where you explicitely mentioned Nordmark´s publication you stated (correctly) it was from 1976.
Usually - as additional confounders are excluded - participants in these kind of tests are more sensitive to interaural time differences when using headphones.
Nordmark was especially interested in the impact of jitter (variation of the pulse gap width) on the sensitivity for ITDs.
I have to reread the paper too, but iirc he found the same low threshold even for high frequencies if SPL was quite high and jitter used.
(The number of participants was low,though)
In principle it should be so, but in an experiment it is much easier to calibrate for a small initial phase mismatch between channels as it is for a loudspeaker-in-room setup.
Accordingly other experiments using headphones and loudspeakers found diverging numbers for each case. Choisel/Martin for example reported fairly constant mean of 50 degrees (interchannel phase mismatch) wrt frequency for loudspeaker usage while higher variation for headphone usage, but the numbers converged for higher frequencies (above 3-4 kHz).
So - wild speculation too - it could be that at higher frequencies the loudspeakers were more beaming and therefore less reflections confounded the results.
Overall Choisel/Martin reported also results around ~7 us and emphasized the role of training.
The main difference,as Mmerill99 already stated, could have been the impact of jitter (but i´ve to reread the publications) not to mention the quite different stimuli.
But at a first glance it depends on the descriptions used; a JND (just noticeable difference) is usually the threshold at which 75 % detection is possible. The number reported (i.e. the 6.9us) is based on this criterion and is in addition an average.
Individual response curves indicate that on a personal level some are performing better in these experiments than others and even averaged the numbers are approaching 60% correct responses even at 2-3 us (at least for some experimental conditions).
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Well yes....but the way I see it these are real measureable differences in the wire and although for some it might not make a measureable difference in the end sound but, they very well might be measuring the wrong things.
And as per recent twists in this thread The actual ‘hearing’ seems to have a complex and subjective understanding.....when people don’t understand they dismiss.
I just roll with it
Care to elaborate......fig 8 is a connector style is it not?
I seem to have heard of people using cat 5.....just tie all the wires together?
And what does white have to do with it......surely you of all people aren’t poking fun are ya?
If you have enough of the Cardas, try the Star-Quad configuration: double up, and connect like this:
+ -
- +
Jitter is simply deviation from periodicity. It can be also periodic ( called also frequency modulation) or random, caused by noise or by other influence, e.g poor PSU or other disturbances
And strictly speaking, all errors in a digital stream transport can be called jitter. Like when one shoots a .45 cal through a CD, the resulting missing data merely represents very very very long "T"s which are asynchronous with the recovered EFM clock.
Low signal level causing dropouts does the same...
Have any other nits needing picking?
Cheers,
Howie
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