The "Elsinore Project" Thread

Scott, this is what your own link says:

Electrical impedance | physics | Britannica

"Electrical impedance, measure of the total opposition that a circuit or a part of a circuit presents to electric current. Impedance includes both resistance and reactance (qq.v.). The resistance component arises from collisions of the current-carrying charged particles with the internal structure of the conductor. The reactance component is an additional opposition to the movement of electric charge that arises from the changing magnetic and electric fields in circuits carrying alternating current. Impedance reduces to resistance in circuits carrying steady direct current."

That is what happens when you measure the impedance of a raw driver in free air.

I am totally on solid ground and this has been confirmed by peers and superiors. That's because it is how we measure the impedance of a driver in the real world, not just theory - and there is no problem with theory, it is in 100% agreement.

But let us leave it there. As I keep saying, this thread is about DIY building and not too much theory.

Cheers, Joe
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Allen, please, don't fall for this. It is how Thiele measured the impedance of a driver with an AC VOLTMETER!

How obvious is that?

This is getting beyond silly, I have nothing to prove.

Don't forget, I live here in Sydney, at one time very close to Sydney University. I did not get to know Neville Thiele, but I did get to talk to Richard Small. I also had a friend, Terry Smith, who was what I would consider a close friend of Neville. My Father had worked for the ABC at Gore Hill and Terry worked at nearby SBS. Terry was a goldmine for me.

Like I said to Scott, I am going to leave theory here.

I will put you on my list to get the paper I am working on, but at first it will be confidential, and even before you read it, it will have had some pretty heavy vetting and it will not be so easy to lazily dismiss it. OK?

Cheers, Joe

PS: Where did you get the idea that Thiele had to defend himself? That is not even on the radar. Sigh.
 
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It is how Thiele measured the impedance of a driver with an AC VOLTMETER!
Really?

I'll tell you what's silly.. having to run after someone in order to preserve context, again and again.

[Rule 12. Improper use of the Quote function such as altering the words or meaning of the quote, misquoting or lack of quote attribution.] ... Quote function or otherwise, the spirit of this is good for the community.

We should be able to discuss Ohms law on our own without name dropping. Shouldn't we??
Joe Rasmussen said:
I am going to leave theory here.
The next time you decide to cite someone from outside the thread I want to see regard for their ideas, and for their wording, even if that means showing references.. and I don't want to see any ambiguity in it, or we'll come right back here.
 
Allen, I'm sorry, but you really disappoint me.

I said I would leave it there. This is a forum, not for ideological squabbles, but for DIY builders. Have I not made that plain?

To say that I have no regard for others and their ideas is something my life and the way I lead it would provide more than just a mere denial. It is a ridiculous suggestion. I always give credit where it due and only hope that others do likewise towards me. So I don't accept that empty assertion. It is simply not true.

ALSO: For some reason I have no 'Quote' option on the last post, I only get 'Reply' - so please for give me, OK?

That is why I haven't used the Quote option in this reply. Again, why does everything have to be misinterpreted in a negative way? Especially when I don't have the option.

See below - I don't know why it is like that.

And for your information, Ohm's Law is at the very heart of the logic. Did you honestly think I was banishing Ohm's Law or even suggesting anything like that, or Thevenin equivalents?

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Joe, I am sure you know your trade, but it's sometimes really hard for me to follow your arguments. I believe things would be much easier to understand if you'd be a bit more careful about the terminology, wording and language context of your arguments. I pointed out a few examples below to illustrate my problems.


Anything above the Re value is a voltage source and here it becomes an impedance, yes, voltage becomes a back-EMF impedance.

Re is a resistance, so it cannot be a voltage source. Re may be considered an impedance, yes. Re cannot become back-EMF, because electromagnetic fields (EMF) are fields, not resistances. By your logic:
Re = voltage
Re = impedance and back-EMF
Therefore: impedance = back-EMF = voltage
This is completely jumbled up.

"There simply is no difference between back-EMF and impedance."

No matter who wrote that sentence (even if it was Earl Geddes or some other "big name"), an electro-magnetic field is something else than an impedance. As it is, this sentence is just pure nonesense to me. I hope Earl provided some context to this, which is missing here.

You know what that does to any theory attached to amplifier's having a 'damping factor' and as to whether it is a Butterworth or Bessel?

An amplifier does not and cannot have a damping factor. The damping factor is the ratio of the (nominal) loudspeaker impedance and the output resistance of the amplifier. The term "damping factor" therefore pertains to the system formed by an amplifier and a loudspeaker. Also, there is no such thing as a Butterworth or Bessel damping factor. Again, this sentence does not make any sense to me.
 
Sorry, but I don't have the 'Quote' function on the last post and replying is a problem.

You make some interesting points, but...

No, based on what has transpired, I would like to respond, but clearly I am now being accused of things I have not done. Next thing I will be accused of ignoring Kirchoff's Law, that always comes soon after Ohm's Law. It's just too silly for words.

Too sad that www.diyaudio.com has become a bitter battleground that it should never have become. Jason Donald, are you hearing me?
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Too sad that www.diyaudio.com has become a bitter battleground that it should never have become. Jason Donald, are you hearing me?
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i also find it strange in this thread that SAME users keep asking and asking basic theory again and again, i just don't get what they are chasing. only to prove that Joe is wrong and you are Smarter??? geeez

if you guys want to debate about Joe's contribution for designing free Elsinore, it's better you make a separate thread with what you want to debate so others will jump into the "battleground", not keep spoiling in this thread.

Joe, i also suggest you stop to entertain this endless debate. no benefit to all users who have built Elsinore or in progress building like me.
 
Joe, i also suggest you stop to entertain this endless debate. no benefit to all users who have built Elsinore or in progress building like me.

You are absolutely right. That is what the forum is for. So I am consigned not to say anything too much behind the thinking of the Elsinores and how they came about.

BTW, this has been the strangest year of my life. Am I the only one?

Come 2021, may you be a good friend to all of us. :D

Cheers, Joe
 
He could end it any time he chose by showing acoustic measurements, that's what this is really about, his own use of "terminology" is not going to change.

Correct. And my 'terminology' will be proved correct too.

Have anybody come across the this quote below?

"Current Driving of Loudspeakers" by Esa Merilainen, see chapter 3 on page 19. Esa discusses and documents correctly every aspect of motional back-EMF, inductive back-EMF and microphonic back-EMF. See in particular Figure 3.4 on page 28.

On page 27 it says:

"Electromotive 'forces' (EMF) are voltages, by nature, although they are called 'forces.' They can be represented, in circuit, by built-in (AC) voltage sources..."

() added.

Back-EMF are voltage sources. They are not resistance, the back-EMF is in series with the Re (DC resistance) of the voice coil and opposes current, impedes current. The impedance of the driver at any particular frequency is made up of Re in series with... voltage sources.

It's not brain surgery. It is actually what it is. Talked to many others who have figured this out. And it is not new, it is not incorrect wording, it is precise and actually backed up solidly by maths. Ohm's Law is not threatened, neither is Thevenin's equivalents nor Kirchoff's Law. :D

That was the last comment on the matter here.

If you don't agree with Esa either, then too bad. You are not just disagreeing with him and myself. There are others who understands this.

Physics and science always gets there in the end.

Ciao.