Bruno Putzeys paper on Negative Feedback

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I know the Merilainen book. There is a difference in the approach: he can only use a commercial product off-the-shelf I can get one better.
I repeat, getting a linear behavior is the real thing. All the rest is peanuts....

Why do you always change the subject or move the goal posts? How on earth can you have a useful discussion this way?

Jan
 
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45 said:
Ehmmm but according to DF96 it should be obvious!
It should be obvious that you can't make a nonlinear system by combining linear systems, but sadly it appears that this is not obvious to some people.

He knows everything....!!!
Unfortunately this is untrue. Mostly I talk of things I know. When I stray into areas I don't know so well I can be sure that someone will correct me, and if they do that with good humour then I am grateful.

He knows that for voltage drive a specific driver is needed and for current drive another kind of driver is needed.
I never said that. I do believe that you need a different speaker design, to have different damping, but not necessarily a different driver design. Why not address what I say, and not what I do not say?

What does this mean? It doesn't mean anything. Total nonsense. There is no specific requirement. The same driver can be succefully used with both!!
As I didn't say it I do not need to defend it.

Well, if you have current drive there is no (or minimal in real case) back EFM which is a feedback form.
There is still plenty of back EMF, but the amplifier ignores it. You could argue that it is the voltage drive which gets no back EMF, because the EMF has to be lost across the driver resistance as it cannot impose a voltage across the source (because the source has zero impedance). I am puzzled why so many of your technical statements seem to be the exact opposite of the truth.
 
It should be obvious that you can't make a nonlinear system by combining linear systems, but sadly it appears that this is not obvious to some people.
Again with this obvious thing. You haven't provided any explanation for the obvious so far.

I never said that. I do believe that you need a different speaker design, to have different damping, but not necessarily a different driver design. Why not address what I say, and not what I do not say?
I don't think so. You do need different driver design in the first place but it is all about linear behavior.


There is still plenty of back EMF, but the amplifier ignores it. You could argue that it is the voltage drive which gets no back EMF, because the EMF has to be lost across the driver resistance as it cannot impose a voltage across the source (because the source has zero impedance). I am puzzled why so many of your technical statements seem to be the exact opposite of the truth.

When I wrote there is no back EFM it was referred to the amplifier. I didn't say anything different.
If statements are taken out of context they can become everything, including the opposite.
 
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45 said:
Again with this obvious thing. You haven't provided any explanation for the obvious so far.
I am afraid that this is one of those things which is either obvious or beyond your understanding. Linearity contains no nonlinearity, so cannot produce nonlinearity. Try to make a nonlinear equation by linearly combining linear equations - it cannot be done.

45 said:
You do need different driver design in the first place but it is all about linear behavior.
Would you please make up your mind? You criticised me for allegedly saying that a different driver was needed (which I did not say) now you say that a different driver is needed. Why is something "total nonsense" when you think I said it but is now perfectly sensible when you say it?

45 said:
When I wrote there is no back EFM it was referred to the amplifier. I didn't say anything different.
But the full back EMF appears at the amplifier terminals. You said there is no back EMF. Perhaps what you meant to say is that the back EMF is present but ignored in current drive?

45 said:
If statements are taken out of context they can become everything, including the opposite.
"Statements taken out of context" is the classic excuse offered by politicians and other public figures when they say something which is false or considered wrong (or even unsayable in this current illiberal political/social climate) and they know that they cannot deny saying it.
 
I am not changing anything. I just have a different approach.
Also a 100ohm-to-1K Zout amplifier is not really a true constant current amplifier but is gets close. 1 Mohm is.

Yes you are. First you state that the same driver can be used for voltage or current drive. When I mention that Esa Merilainen and others have found that you need different optimized drivers for the two situations, you go on about the book, you say 'I repeat, getting a linear behavior is the real thing. All the rest is peanuts.... ' and start about output impedances.

Can I ask you, why are you here? Do you want to have a discussion where everybody gets smarter, or you just want to throw out random statements and the hell whether they make sense or not? We have a lot of patience to explain things but not if it is not appreciated.

Jan
 
I am afraid that this is one of those things which is either obvious or beyond your understanding. Linearity contains no nonlinearity, so cannot produce nonlinearity. Try to make a nonlinear equation by linearly combining linear equations - it cannot be done.
You are just groping in the dark and go on with this nonsense. I never said that a non-linear equation results form linearly combining linear equations. You are clearly missing one term in completing the equation and that's what introduces non-linearity. So I am afraid there is nothing obvious. End!

But the full back EMF appears at the amplifier terminals. You said there is no back EMF. Perhaps what you meant to say is that the back EMF is present but ignored in current drive?
Yes. I also added that likely that sort of amplifier was cited having in mind a different perspective (i.e. it is an amplifier with no NFB).
 
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You are just groping in the dark and go on with this nonsense. I never said that a non-linear equation results form linearly combining linear equations. You are clearly missing one term in completing the equation and that's what introduces non-linearity. So I am afraid there is nothing obvious. End!


Yes. I also added that likely that sort of amplifier was cited having in mind a different perspective (i.e. it is an amplifier with no NFB).

You said that when you have two linear 'things' and combine them the non-linearity occurs. I hope you have enough self-respect to refrain from 'no I didn't' and make me look it up and proof you a liar.

Jan
 
You said that when you have two linear 'things' and combine them the non-linearity occurs. I hope you have enough self-respect to refrain from 'no I didn't' and make me look it up and proof you a liar.

Jan

If fact I didn't say linearly combine them. It doesn't happen! What does it mean? There is something else to be considered that is not negligible if I control the voltage and it is, with very good approximation, absent if I control the current.
Now that I have accused to be a liar you can wonder forerer.
 
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