John Curl's Blowtorch preamplifier part II

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You, i presume.
With so little ego, you surely have something to hide.;)

Yes, good to know someone hates me. Too bad making simple observations is taken as criticism, I don't have a copy of Ron's paper and have made no attempt to get one.

BTW I think the correct spelling is Caldonii, though I always fancied myself an Austrian Celt it might be fun to be one of those Picts all painted up with indigo. Trick or treat you know, I even have a tube of real Mayan blue recently recreated from pigment found in ancient sacrificial pits. It's the same as woad/indigo.

<don't bother asking>
 
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Too bad making simple observations is taken as criticism.
Thanks to all this marketing bulls..., audio technology had slowly turned in a kind of religion. With his fake gurus, politically correct way to talk and orthodox (mean mysterious) way to think.
Take care, man, you are on a wrong way, with your calculations, your electric formulas and your scientific knowledge that everybody can access in school books !

What ? You designed Op amps with less than 0.00x distortion and >1000V/µs of slew rate ?
Everybody knows that Integrated circuit OPA does not sound. (i believe it is because the plastic around the chip witch eats the sound, they do not take the memory of Silicon in consideration, they are not cryogenic threated AND they are not expensive enough).

How can you ask questions about the new secret discovery of the last mysterious effect, while you don't know the SECRET ?

On my side, I made ​​amends, and don't slept last night. I can't even listen anymore music on my system, (with no phase turn in the audio bandwidth), because this new discovery of phase modulation by the offset.
In the same time, i don't wonder my computer runs at 5Ghz, its motherboard able to power the cpu with 3V >50amps and no ripple, able to record and play audio programs at a sample rate of 352,8Khz for near no money. It is digital, it does not sound !
 
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What is a common mode for an audio signal? Do you mean an amplifier connected for non-inverting gain. Common mode and DC for air pressure as it relates to the propagation of waves doesn't make much sense. I suppose popping a balloon in a sealed room would leave a change of DC pressure.

The statement that AC coupled asymmetric waveforms have a net DC component keeps coming up like it's a fact.
Ditto to Guru Wurcer & Guru Cordell too.

.. with my (pseudo??) Signal Analysis, DSP & microphone guru hat .. :D

Christophe, the answer to your problem is simple. Only use stuff that is hand carved by virgins from solid Unobtainium. :)
 
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Imagine my desesperance. Since the subprimes, in Europa, we have no more access to Unobtainium. It was produced in Greece.

You mean it was consumed in Greece

In any case, don’t look me with an envy eye.
Me too failed to stock any. :D

And I love dissecting old TV sets from the streets, collecting components for the non ending list of future wanna be projects :p

George
 
Thanks to all this marketing bulls...

Christophe, I have found this strong talk to be counter-productive. Let's wait and disscuss the data, the TL071 is certainly better than a 741 but why not something from the last 5yrs. pretty easy to find even two orders of magnitude better? And how about the relatively poorer performance of some of the audiophile certified class A circuits that Jan alluded to? If PIM is as bad as jitter (that's IF) then it applies here too, yes, no?

Personally I don't think this will lead anywhere but at least there is some technical content.
 
the TL071 is certainly better than a 741 but why not something from the last 5yrs. pretty easy to find even two orders of magnitude better?
Yes, i found 741 pretty bad for audio, and don't used-it at its time. In the same time we were yet aware of commutation speed induced problems while we were using planar power transistors since 1970 instead of 3055.

While TL071 was quite correct as long as you didn't asked him too much output current, it was not so good for mix stages of desks. Used in inverting mode, its gain increasing each time a slide of the desk was added, it was easy to feel the lost of transparency as much as the gain was increased. Then appeared those nice Current feedback Op amps...15/20 years ago ?
End of the story, no more problem. Thanks to this 500V/µs.

What is counter productive ? To speak about feedback as "something bad" for audio, as a lot of gurus did at this time, or try to understand, and explain, how behave closed loop systems, as Bob Cordell did, in the same time ?

Notice i made no reference of IM (TIM or PIM), while it is everywhere behind.
Did i understood well what was in your mind ?
 
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diyAudio Member RIP
Joined 2005
On this site, how do we distinguish sarcasm from sincerely-held beliefs? No opinion seems to be so barmy that nobody holds it. Of course, some of us can tell some of the time just from who said it but that doesn't always work. Should we use a mandatory emoticon when we say the opposite of what we actually believe?

At my boyhood pal's home, the Duttons had a practice of holding the forefinger in the air when they meant something to be taken as sarcastic. Of course gestures with the hands have wildly different interpretations in different cultures and at different times. Some of the misconceptions found their way into advertizing --- many Italians are still laughing about the old images of "Chef Boyardee", the cartoon depiction based on a real chef, holding his hand up making a circle with thumb and forefinger, which had a very different meaning than intended.
 
Notice i made no reference of IM (TIM or PIM), while it is everywhere behind.
Did i understood well what was in your mind ?

No problem, I certainly understand the Dr. House like sarcasm, but I think there is some real technical meat on the operating table here with Ron's second paper. There might even be a couple of freight trains on the same track in opposite directions.
 
To Scott, at first degree, this time.
I love Integrated Circuits.
I use them as often i can find a OPA witch reach my needs.
They simplify my work, their little surface present a lot of technical advantages, and, thanks God, do not allow easily caps inside.
Please, re-read my message, all of it was second degree, except the first sentences.
It was a credit to all those guys, working anonymous in laboratories, like you, i believe, because i remembered your name at the bottom of some of those luminous (clear, complete, and often elegant) data-sheets and enjoyed so much your products.
About the ron's paper, i do not now about. And don't have any doubt some things are interesting inside. Just i do not reason that way any more, with kinda schizophrenics concepts.
All my reasonings are time correlated, when it is about audio. Delays, levels, order of magnitude. And my measurements to track how they correlate together.
 
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