And how can you be sure what you see
A major reason I don't watch much TV is because I am sadly quite aware of what's on the screen. I used to think American TV was uniquely bad until I started going to Europe regularly.
Maybe he's just a mortal, human being like everyone else, and as such, just as susceptible to the weaknesses of mortal, human beings.
se
Hi,
Funny, I used to think European TV was bad. Then I got to the US frequently. I used to think the lowest common denominator in europe was low (TV by it's nature is that), but the one in the US can walk under a snake wearing a tophat.
Anyway, I find TV very educational. Whenever someone turns the set on I go to another room and read.
Ciao T
Funny, I used to think European TV was bad. Then I got to the US frequently. I used to think the lowest common denominator in europe was low (TV by it's nature is that), but the one in the US can walk under a snake wearing a tophat.
Anyway, I find TV very educational. Whenever someone turns the set on I go to another room and read.
Ciao T
Sure, but you possibly missed all those posts here that said that whatever you do to get wide ol bw, INCLUDING resistive loading of the Vas, is the best thing since sliced bread. Marcel's letter was triggered by that. We know YOU know better
jan didden
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I may take you up on it someday. For this crowd fuzzy images go fine with fuzzy thinking
Never a jpg! It's really very simple. Just print the AP graph, set the parameters, line width, color, size, what have you.
But print to a virtual PDF printer, NOT you your regular printer. Download & install Bullzip PDF and print to THAT. You get fully customizable razorsharp graphs even if you blow them up to 2 x 3 feet size.
And ohh yes, increase the font size for the axis scales by 50 to 80%, that will really make it look professional on the printed page.
You're welcome.
jan didden
Wow...! At present I'm playing with an headphone amplifier based on a current feedback (or mode?) architecture working open loop - it's a pretty textbook topology (diamond buffer in - current mirrors - power diamond buffer out), but its performances are amazing. To be clear: nothing against VF closed-loop architectures, but I was intrigued by the opportunity to hear the open-loop sound (and to easily compare it the closed-loop one, too), so I decided to give it a try. I'm not planning to get a 'Class-A' from Stereophile, nevertheless it seems to sound very good...
L.
Charles,
The problem I have is when you or John issue statements based upon what you hear.
It is just a coincidence that virtually any of the things you guys comment on correlate well with tests I have done?For example:
Both John and you mention using Resista resistors which measured the best of any very low cost carbon film resistors I tested. But of course the difference between the best and worst is at levels some seem to think doesn't matter.
You recommended larger cans for the same value of capacitor to sound better, it turns out they have much better vibration and leakage characteristics.
You mention using power line filters slowly changes the nature of power amplifiers sound. I record that inductors and transformers on normal AC lines do very slowly change.
John uses "flatpak" transformers, they have the lowest RF passing of any I have tried.
John does a number of extraordinary steps in the Blowtorch power supply, all of which have measurable results although at a very low level.
Now someone comes along and lets me know that the 5534 op amp is just as good as others. I didn't like the sound of it in many applications, Sam Groner using Walt Jung's techniques finds it not as good as many and You and John suggest not using it.
So the great question is will you and John continue to give us this obviously opinionated advice? And do you do all this by ear?
ES
Great, I'll have to try it. Of course my AP2 is starting to get to me on how long it takes, so I may move on!
I believe that there are audible deficiencies intrinsic to all ICs. Furthermore, I believe that the greatest problem is due to the use of negative feedback. We have achieved excellent sonic results with the AD844 by using it open loop, but it still isn't quite as good as a virtually similar discrete circuit. However, it is much simpler and easier to use and takes up much less board space.
We would design it into many more products except for the fact that around 2002 or so, Analog Devices moved production from a 4" process to a 6" process (probably at another fab house). Ever since, about 20% of the devices don't meet the noise spec. We have to measure each one on a QuanTech noise analyzer and throw the bad ones away.
It is easier to build a discrete circuit than go through all of that brain damage. Plus the discrete circuit sounds better.
~~~~~~~~~
But enough about me, you big hunk!
Tell me about yourself...what is your theory that accounts for John's (and dozens of other designers') findings?
I don't spin theories without evidence; all I have at this point are hypotheses. If you're willing to try to demonstrate these deficiencies by ear alone (John stoutly refuses), I'd be delighted to collaborate with you to set up controlled subjective experiments to validate (or falsify) your hypothesis. If not, I understand- you have product to sell, and there's no upside for you, other than the glory of being the guy who finally settled Lipshitz's Great Debate after 30 years of null results. Glory doesn't pay the rent, as I sadly am aware.
Charles,
The problem I have is when you or John issue statements based upon what you hear.
For example:
Both John and you mention using Resista resistors which measured the best of any very low cost carbon film resistors I tested. But of course the difference between the best and worst is at levels some seem to think doesn't matter.
You recommended larger cans for the same value of capacitor to sound better, it turns out they have much better vibration and leakage characteristics.
You mention using power line filters slowly changes the nature of power amplifiers sound. I record that inductors and transformers on normal AC lines do very slowly change.
John uses "flatpak" transformers, they have the lowest RF passing of any I have tried.
John does a number of extraordinary steps in the Blowtorch power supply, all of which have measurable results although at a very low level.
Now someone comes along and lets me know that the 5534 op amp is just as good as others. I didn't like the sound of it in many applications, Sam Groner using Walt Jung's techniques finds it not as good as many and You and John suggest not using it.
So the great question is will you and John continue to give us this obviously opinionated advice? And do you do all this by ear?
ES
Yes, Ed. It is much easier to do it by ear. And you actually achieve what you are aiming at -- knowing what sounds best. I will freely give some of it away. Other parts I keep for myself.
It's nice that you have found tests that correlate with testing by ear. But if you didn't have the "subjective" tests already, how would you know what would sound better just by measuring it? I think the best case you can make is to corroborate the listening tests.
The "Resista" has mutated over the years. It was first recommended by J. Peter Moncrieff in the '80s. By the time we started using them in the '90s it was actually made by Draloric. I don't know if another company made them previously. Vishay bought Draloric. Everything was fine until Vishay also bought Beyschlag, a nearby competitor. After a while Vishay closed the Draloric factory and now all of the "Resista" resistors are made by Beyschlag. They don't sound quite as good as they used to, but they are still amazingly good for $0.01 each!
Your resistor tests essentially were tests for TC. I think there is more to the story than that. I know that for a long time there were people that said the larger wattage "Resistas" sounded better than the small ones. I never found that to be true. We compared the smallest one they made against the standard size one and could hear no difference. None.
While many people have recommended using larger physical sizes of electrolytic capacitors, it wasn't me. I don't dismiss the possibility, but I have never done the test to see if it is true.
Regarding power line filters, my comments on them changing over time have been restricted to ferrites. Specifically they somehow become magnetized, and that somehow affects their sonic performance. I have no explanation at all for either "somehow". However I know both to be true because demagnetizing them with a bulk tape eraser restores their original sonic performance.
In addition, I invented a completely non-magnetic device that performs the same function as a ferrite -- it separates the RFI riding on the power line and dissipates it as heat. This device sound very much like a freshly demagnetized ferrite, except that it never changes its sonic properties.
SY, just for clarity, I have consistently refused to let YOU set up a test, that will ultimately come to being NULL, just because you want to put me in that position. I KNOW my limitations, and know that I am distinctly lousy at ABX type double blind tests, although others have been shown to do better, in my presence.
I was given a piece of advice by Dr. Rod Rees, two decades ago, who advised me to never participate in a listening test set up by people who don't believe in many listening differences. He was a professor at the time, teaching 'History of Science' and similar topics. I will stick to his advice. Articles by Dr. Rees can be found in 'The Audio Amateur' from 1979 (or so) for the next several years. He also gave up trying to 'reason' with the double-blinders, although he made a serious attempt to do so, early on.
I was given a piece of advice by Dr. Rod Rees, two decades ago, who advised me to never participate in a listening test set up by people who don't believe in many listening differences. He was a professor at the time, teaching 'History of Science' and similar topics. I will stick to his advice. Articles by Dr. Rees can be found in 'The Audio Amateur' from 1979 (or so) for the next several years. He also gave up trying to 'reason' with the double-blinders, although he made a serious attempt to do so, early on.
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