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Old 23rd February 2004, 02:29 AM   #11
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Hello -

I give up. I'm done with this thread.

Charles Hansen
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Old 23rd February 2004, 02:48 AM   #12
Eva is offline Eva  Spain
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I still have tons of doubts

First, I don't understand how the presence or absence of feedback could produce all those mysterious artifacts on the waveforms only perciveable through the ear but not through measurements or even nulling tests [substracting compensated output from input]

Second, I don't understand how this magical difference between 'short-loop feedback' and 'long-loop feedback' could also cause mysterious non-measurable but audible waveform alterations. Is it a real functional difference or it's just a cosmetic difference?

Third, if a signal is not measurable, I don't understand how could it be recorded into a disc [How do we represent unmeasurable signals in the digital domain?]

Fourth, could a non-measurable voltage cause a non-measurable current to flow through the voice coil of a loudspeaker in order to produce a non-measurable force over a diapraghn to create a non-measurable pressure gradient capable of reaching your ears and stimulating your cells in a non-measurable way?

[By 'non-measurable' I mean the case when measurement equipment says the magnitude is zero or negligible]

Fifth, how we could talk about 'no feedback' when bipolar transistors have internal feedback mechanisms like : Miller capacitance from collector to base, current gain that decreases as Vce decreases or Ic increases, and Vbe that increases as Ic or Ib increase? [every gain device has his own internal feedback mechanisms]

My theory is that only measurable acoustic signals exist, and thus, non-measurable differences perceived as 'acoustic' are not due to acoustic signal changes but due to differences in the whole enviromental perception [ie: Everything sounds to me less bright and with less resolution when I'm tired or I'm having a bad day, and imaging perception changes when I turn off the lights]
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Old 23rd February 2004, 03:35 AM   #13
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Quote:
Originally posted by Charles Hansen


Well, yahbut... what does Bischloroethyl Nitrosourea have to do with open seater sports cars?

Charlie
The car is from the British TV series "The Prisoner". Jocko was quoting the series. "I am not a number. I am a free man."

"Who are you?"

"The new No.2."


JF
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Old 23rd February 2004, 03:46 AM   #14
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Hello John-

Thanks for the explanation. I'm proud to admit that I don't have a TV, so I don't really know what that show is about. I'm embarrased to admit that it took me this long to realize that "BCNU" means "be seeing you"...

Armed with your information about the TV show I was able to determine that yes, that car is a Lotus Super 7. Nice ride!

Thanks,
Charles Hansen
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Old 23rd February 2004, 03:56 AM   #15
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Quote:
Originally posted by Charles Hansen
I'm proud to admit that I don't have a TV...
: )

BTW: Thanks for your contributions to the forum.


JF
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Old 23rd February 2004, 05:17 AM   #16
AKSA is offline AKSA  Australia
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I have watched this thread move off onto semantics; the heady issues related to the definition of negative feedback, etc. Much of this mess, I will admit, is the fault of overzealous marketing departments.

However, when someone of manifold, deep experience such as Steven, Pavel, Charles or Terry comes along and offers their two bob's worth, must they be always obliged to prove that their opinion is legitimate, that they have sufficient experience, and are worthy to post comments? One can normally tell within a couple of sentences if someone knows what he is talking about, or has something useful to say. We do not need referees!

Steve, you have hijacked yet again another thread by dissolving it into semantics and proof of authority. Why do you do this, and earn the universal contempt of almost anyone with anything worthwhile to say? You've done it to countless worthy individuals, and caused me and others to list you on 'ignore'. I don't mind admitting I'd throttle you if you came my way, even today. I see a thread going along nicely, your name jumps into the fray, and suddenly everyone is bothered, particularly the person on whose word we are all hanging......

I find myself wondering about your early background......

Cheers,

Hugh
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Old 23rd February 2004, 06:46 AM   #17
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Quote:
Originally posted by AKSA
I have watched this thread move off onto semantics; the heady issues related to the definition of negative feedback, etc.
You say that as if semantics is of little or no importance to this thread.

What's the topic of this thread?

Is there anybody built a non feedback amplifier??

How can that question be answered in any meaningful way unless there is some agreement as to what constitutes feedback? How does the ambiguity of multiple notions as to what constitutes feedback serve the original poster?

Quote:
However, when someone of manifold, deep experience such as Steven, Pavel, Charles or Terry comes along and offers their two bob's worth, must they be always obliged to prove that their opinion is legitimate, that they have sufficient experience, and are worthy to post comments?
Excuse me? Charles never stated that the Sziklai has more negative feedback than the Darlington as an opinion. He stated it as fact and then got all bent out of shape because I questioned his claim.

Quote:
One can normally tell within a couple of sentences if someone knows what he is talking about, or has something useful to say. We do not need referees!
I don't know what you mean by "referees" but if you mean those who don't unquestioningly swallow the claims some people make simply because they have "credentials" I disagree.

Take the cable distortion measurements thread for example.

Charles pretty much dismissed the measurements made by Bruno Putzeys.

What was his argument?

He stated with absolute certainty that the Audio Precision System One was not capable of doing the same type of distortion measurement that John Curl was making using his Sound Technologies distortion analyzer and his HP spectrum analyzer and he was pretty certain that the Audio Precision System Two Cascade was not cable of it either. Ergo, Bruno's measurements could not be compared to Curl's.

Well, Charles said that he's owned (and one would assume used) an Audio Precision System One for over 10 years. So obviously he would know what he's talking about when he says that it can't make such a measurement, yes?

I've never owned or used any Audio Precision system but it took me just 20 minutes or so perusing the System One's owner's manual to discover that it could indeed make the same type of distortion measurement that John was.

I'm not saying I'm a genius and Charles is an idiot. Simply that Charles, despite his experience and "credentials" is human the same as all of us. And that no one should ever be intimidated by "credentials" to the point that they never question or otherwise challenge claims made by certain people.

Quote:
Steve, you have hijacked yet again another thread by dissolving it into semantics and proof of authority.
If the claims I questioned did not constitute "threadjacking" then I fail to see how my questioning them are.

Quote:
Why do you do this, and earn the universal contempt of almost anyone with anything worthwhile to say? You've done it to countless worthy individuals, and caused me and others to list you on 'ignore'.
In my opinion, "worthy individuals" don't throw childish temper tantrums because someone may question some of their claims or disagree with them.

Worthy individuals don't expect their claims to be swallowed without question.

Worthy individuals welcome questioning and challenging and are more than happy to substantiate their claims.

Worthy indivuduals welcome dialogue and even argument because they know that these are filters by which we get closer to the truth.

This is because worthy individuals aren't so full of themselves that they can't conceive that they could ever possibly say anything which is incorrect and don't seek out nothing but unquestioning sycophants to impress.

Quote:
I don't mind admitting I'd throttle you if you came my way, even today.
You'd throttle me if I came your way and you wonder about MY early background?

I rest my case.

se
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Old 23rd February 2004, 10:11 AM   #18
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Quote:
Originally posted by Jocko Homo
It is not a matter of protection.

Some people just aren't interested in hearing stuff that runs counter to their mind set.

Jocko
Jocko, does that include those people who refuse to accept that National got the soft start circuit right in their datasheeet? Or those that refuse to accept that the circuit works as confirmed by DMMs?

Just curious.
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Old 23rd February 2004, 10:30 AM   #19
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Quote:
Originally posted by AKSA
However, when someone of manifold, deep experience such as Steven, Pavel, Charles or Terry comes along and offers their two bob's worth, must they be always obliged to prove that their opinion is legitimate, that they have sufficient experience, and are worthy to post comments? One can normally tell within a couple of sentences if someone knows what he is talking about, or has something useful to say. We do not need referees!

Hugh
I disagree with you on this, Hugh. We are here to better our knowledge about audio and learn from each other. Everyone is equal, including those with more experience. This is not the animal farm where some of us are more equal than others.

Charles may have a lot of experience in audio. But that doesn't mean that he could be foundamentally wrong in his line of work (we have seen that in the lm317 soft start thread, haven't we?).

If he holds the truth, he should not be afraid to share with us and defend his position. So far, he has not been able to demonstrate that, in my view.

That is not to say that Charles is a lesser person. It is that his view did not hold up in a debate.

No, we don't need referees, but we do need truth.
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Old 23rd February 2004, 10:32 AM   #20
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Quote:
Originally posted by Jocko Homo
then go build one and tell me I am wrong.

I'm not.

Jocko
that's a lot of preconceived notion right there.

Yes, Jocko, you are very very wrong.
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