You mean, true coax?
As in coaxial cable...single core coax??
Or do you mean mike cable, which Ed did NOT show correct measurements of. Yet, the discussion was about mike cable..
Or, do you mean some arbitrary shielded speaker cable, of some arbitrary length, of some arbitrary spool diameter, at some arbitrary frequency.
WITHOUT REGARD TO ACTUALLY MEASURING IT PROPERLY? You do know that the shield floats, no? What, 99 pf per foot, whereas the conductors are 55 pf per foot, right? Did Ed try to guard the measurement? Can his equipment perform a 3 terminal guarded measurement?
So, do you really think I'm going to play some childish guessing game you come up with? Really?
Go back and read what I said about testing the red mike cable I have and when I was going to do it.
So, to sum up...test what? Ed did a bait and switch with no test parameters, no test design, no understanding of accuracy, no baselining of the equipment.. Just some undocumented pictures showing lord knows what.
You do understand the distinction between a shielded twisted #14awg pair and a cylindrically shielded mike cable with fillers to make the shield conform to the cylinder, right?
And simple coax? It doesn't magnetically couple no matter what the ratio of coil circumference to twist pitch, as coax had no twist pitch. You didn't realize that?? (I discount helically pitched unbraided shield, as I suspect everybody does.)
Better yet, answer me this: Malcolm published his paper in 1986, right? In the intervening 27 years, has anybody else on the planet reproduced his results? Anybody??
You've talked about high order distortion of simple rca's using your ST device, yet in the intervening years, nobody has duplicated your results...many have tested further into the mud and found nothing using better equipment however...why is that John???
As I said, test repeatability is key.. I don't waste my time trying to reproduce unreproduceable tests that are not detailed so that they can be duplicated. That may be your game, it is not mine.
And here I scanned the page I started to put together detailing in pictures what I intend to do...sheesh, that's gratitude for you.
jn
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Now you're rubbing it in, happy New Year to all.
You too Scott.
You know, to this day I still can't figure out how that multiplier works.
Looks like some kinda transmission line thingy..Gimme caps and diodes anyday..
john
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Quoted liberally in the AD8010 datasheet. This different take on bypassing was the result of 2 weeks of board building and experimentation. The diff-gain diff-phase performance for a little 8-legs into 18.75 Ohms was remarkable and at 4.43MHz was demonstrably limited by circulating supply current issues.
EDIT - C1 and C2 are composite caps detailed in the text as well as the vendor on the ferrite beads.
EDIT2 - jn this was 1998
What is special with this arrangement Scott?
C1 has been discussed here in the past, it’s function (helping by locally circulating unbalanced supply current btn +/_ power pins) has been debated (I keep on using it).
C2 seems orphan without it’s counterpart at the + power pin but it’s there as the PSRR ref – line is ~10db worse than the + line at frequencies below 1MHz
Happy New Year to all (113 minutes remain here and down-counting )
George
>Edit.
PS Last years diyaudio.com statistics showed the highest traffic peak occurring during the first hours of the then New Year. I am curious to see if this will be repeated again
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Wonderful.
What kind? Mike cable as per the discussion and what I detailed as part of my tests?
Or the one that was swapped in, as in bait and switch?
Does it need to be yellow? Or can I use the red one I stated I was going to measure?
What coil radius?
What length?
What twist pitch?
Do I find a meter that barely functions at the range required, or am I allowed to use a good one?
Am I allowed to use the meter in the way HP intended, or do I have to use an incorrect setting that gives numbers 3 orders of magnitude out? You know, like a "practical engineer" you claim to be.
What frequency?
Do I spool it such that the centroids are at least 5 spacings away to prevent turn to turn communication?
Or randomly so that the readings can be cherry picked to support my beliefs.
Do I drop in a 4 inch diameter steel cylinder into the center to detect solenoidal field enhancement, or do I ignore that salient aspect of the discussion.
Do I drop in a 4 inch Aluminum cylinder in the middle to reduce the solenoidal field, or do I ignore that aspect as well?
The clear assertion has been that a mike cable coiled will increase solenoidal inductance (remember, that is what Ed stated to justify his three orders of magnitude out inductance measurement). The last two test aspects are intended to play with that.
John, I've already detailed at length the specifics of the tests I will be performing, the materials, the confounders, how to monitor test accuracy, what to look for.
Obviously, you do not understand any of this, so you need to pay attention when this stuff is discussed.
While Sy claims to be the one staring and drooling, it's clear that it's not him.
You have a lot to learn.
happy new year.
jn
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99% of all datasheets show simply bypass on each supply to ground, I'm confused. This did not work here.
From the 8010 datasheet, pg. 9 -
There is no simplified schematic included to clarify further.
"... It was found that the conventional technique
of bypassing each power pin individually to ground can have an
adverse effect on the differential phase error of the circuit. The
cause of this is attributed to the fact that there is an internal
compensation capacitor in the AD8010 that is referenced to the
negative supply."There is no simplified schematic included to clarify further.
Why would I troll. No need to.
My point is what reviewers look for / want is not necessarily in any way connected to good audio engineering.
Example: review of Zanden CD player that got a substantially positive endorsement in the subjective listening test and was subsequently sleighed in the technical review.
What about the ones receiving negative subjective reviews and positive technical review ...
What about the ones receiving negative subjective reviews and positive technical review ...
Generally, they need a better story and obeisance to current fashion statements.
Remember, the word "subjective" as used in that context doesn't mean "subjective," it means "evaluation with eyes and preconceptions." I remember for a time that The Audio Critic would look at speakers and if they didn't use a KEF T27 tweeter, they got slagged. Of course, that was then, this is now, and as with all fashion, judgment standards change.
I think the underlying issue is that technical excellence does not necessarily equal good subjective response. The subjective response usually has very little to do with fidelity to the original. Instead of mocking either good measurements or bad perhaps we should be exploring how the products that yield "good" subjective results and perhaps adding those errors to technically correct products will result in a better subjective result. (I think Pioneer reverbs can still be found on fleabay.)
I know from experience adding reverb and dynamic expansion can produce a positive subjective result. Perhaps something like thermal tails or power supply recovery after a burst could have some of the dynamic expansion that enhances the perceived quality. Neither problem would show on a conventional test and both would possibly add a small but audible effect. If finding the right effects, especially without either knowing or understanding them, is required of high end audio, too much knowledge becomes a burden.
I know from experience adding reverb and dynamic expansion can produce a positive subjective result. Perhaps something like thermal tails or power supply recovery after a burst could have some of the dynamic expansion that enhances the perceived quality. Neither problem would show on a conventional test and both would possibly add a small but audible effect. If finding the right effects, especially without either knowing or understanding them, is required of high end audio, too much knowledge becomes a burden.
What about the ones receiving negative subjective reviews and positive technical review ...
And then there's WAVAC.
The little 8-legs don't get a ground connection, if you follow Paul Brokaw's app note concerning the usual connection of the comp cap to the minus rail which is supposed to be an AC ground it should be clear.
Hasn't worked for me, subjectively either and long ago abandoned.
One of the reasons I think for SQ degradation is not separating signal and power grounds - the rail to gnd capacitors might work fine so long as power ground is kept separate from signal. But classB circuits dump nasty haversine currents into the rails, the noise couples to gnd via the 'decoupling' cap. A 19 ohm load as here is exceptionally harsh. Would biassing the AD8010 into classA help (CCS on output) ?
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