Joe
Got your private message. First of all, no more private messages. Say it in public. Secondly, SY has very tight definitions when he disparages some thought or action. Reading Jans' posts and sims, Your intro to the thread is wrong. Your answer is to double down. It's not a smart thing to do.
Got your private message. First of all, no more private messages. Say it in public. Secondly, SY has very tight definitions when he disparages some thought or action. Reading Jans' posts and sims, Your intro to the thread is wrong. Your answer is to double down. It's not a smart thing to do.
Are we not all?
I have Esa's book only a few feet away and I have also been in contact with Esa. My position is not exactly the same as his, I don't want to design speakers that only work with current, indeed I am not on any crusade to change the world to current drive.
You mention a number of driver limitations, which are exactly the ones I brought up earlier (you must have missed them) including voice coil overhang, so I am a little bemused as you must gather.
Did you see also what I said about 'driver destruction' tests that indicated that the thermal spread over the length is not constant and indicates a J-curve, where the front most part of the VC is exposed in front of the front/plate and that heat failure of the VC is most likely to happen there? That since we can track the heat from the front plate/gap, showing that most of the heat is is radiated across the gap, so that the centre of the VC will be cooler and the rear will warmer, but not as hot as the front of the VC. An analysis of that under dynamic conditions should prove interesting. As electrical Q is dependent on the DCR of the VC, what is the affect of the above in the drive of the gap, when the cone is pistonic.
Mind you, if and when I elaborate, anything I say is getting cherry picked and given 'flat earth' criticism. But yes, I believe that you have actually pointed to some of the very things, and more, that you have, and yes, I believe they do have an influence on the sound. Others here don't see that.
Curiously, you are disagreeing with me when I agree with you. Non-linear thermal distortion, add that to the mix as well. But there is nothing 'self-deceptive' when I there are plenty of others who are listening to this right now? And thoroughly enjoying themselves. Again, some here can't get over that.
And that is exactly what is happening here.
It seems you are having an 'each-way-bet' here?
I say that those vagaries of the driver are better handle because of what you call the 'tank circuit' followed by only series elements afterward a la Esa - indeed much better than one of the alternative crossovers that could be used, which have no way of dealing with those vagaries in any organised way. Just as Esa says, crossovers are not our friends.
So, does this approach suppress problems, even if not perfect? Nothing is perfect, but some things are better.
But thank you for bringing them up... again, as those very same things have been on my mind too.
After I posted this, I received a longish PM. Now, under Dutch law, such writings cannot be published by the receiver, since the copyright is with the author. However, this effectively places me outside the discussion. So, perhaps the author might consider posting his PM for all to read in perhaps a scrubbed version.
Just to make one thing very clear: Joe, for me, this is in no way personal, and I think it is the same for others who are at times critical about some of your ideas. In my most humane assessment, most of the regulars here are way too Asperger to have personal or emotional considerations in technical discourse anyways.
In the case of this thread, you started out all right with your basic concept, being that by compensating impedance variations of a loudspeaker, you can create a "current feedback amp compatible crossover". But then, you introduced some vague, incomplete or incorrect notions.
When you do so in a crowd containing some pretty sharp engineers and scientists, what do you expect? Stop digging.
Ever watched 'Flying High'?
Take your club and stand in line for your wait.
I stand by every perfect and imperfect thing I have said.
But it seems that slander is OK with you? I will use PMs if need be - and I don't mention them on threads as I was told not to. Neither should you. You could have sent me a PM. Your request will be honored.
Frankly, I don't care as long as he answers the questions. The important thing is the technical aspect. So far, all we've gotten is claims that have been shown to be incorrect, followed by excuses, new claims, and gibberish. An actual answer or an admission of error would be nice. The rest of it, who cares, really?
I'm curious if the data files were sent to John K, a genuinely smart guy who generously offered to help out here.
When I send PMs to others, I never mention them here unless it is expressly understood that I can. I was told by one Moderator on how to handle certain things, so that is what I do. I never swear or use foul language. Not here or in any PM. If somebody suggests I did that in a PM, then I will correct the record here, but make no mention of what others said in their PM. Surely that the correct way.
I have never called anybody a quack here, or huckster, or charlatan, a swill, a mere parts seller (I don't sell parts) and even worse. I have been called that, but maybe I went a bit far with the 'monkey' comment - but that's about the worst you will ever hear from me. Charlatans are not cute though.
I have never called anybody a quack here, or huckster, or charlatan, a swill, a mere parts seller (I don't sell parts) and even worse. I have been called that, but maybe I went a bit far with the 'monkey' comment - but that's about the worst you will ever hear from me. Charlatans are not cute though.
After all the names you have called me?
Let's face it, you want a scalp, not answers.
You want proof - if you really want it that badly - just do the experiment yourself. I can neither make you nor stop you.
So the ball is now in your side of the park - and from now on I don't want another escalation between you an me, so expect respectful silence or few words from me to you from here on. That's the best way to keep the peace.
And sorry for the monkey bit - heat of the battle, but I didn't think it was that nasty and happy to see that it was water of a duck's back with you.
Now that seems gibberish to me.
Never heard of peer review - you can do it!
Did I send files to John? No, didn't know he had asked for any.
But I would have to think twice about it. There is such a thing as trust. It's there or it isn't.
Maybe he could give something in exchange?
Nearly 2AM here, bye.
Post 584. If a genuinely smart and honest guy like John offered to help me gratis, I'd jump at the chance.
Joe,
I did not direct my comments to you, they were for those who seem to think that the conjugate circuit is perfect in its response to the emf from the voice coil motion. I for one have chosen to use only under-hung voice coils in my speaker design and can assure you that the inductance is linear in my design. But that does not mean that it still doesn't have any changes caused by voice coil heating with added power, that is just a given with any increase in power. I also have Esa's book at hand.
What I do like about the concept as proposed by the cover of his book is including the moving coil in the feedback loop, that to me is the most relevant aspect to improving the loudspeaker amplifier interaction, baring whether we are talking CFA or VFA as the driving force. I have moved in the direction of direct connection of amp to speaker with all network components before the amplifier. except for that damned cap needed for dc blocking on a tweeter I can see no reason to have any component in between the amp and speaker myself. I am thinking that a push pull application of amplifiers would also be an improvement over the simple single ended amplifier situation that is most prevalent but then we have a second amplifier and a balanced drive so we are into another conversation.
I have made no comment on whether the proposed network as Joe has worked out sounds better or not, I do not have an opinion on that and would need to hear it to make any comment.
I did not direct my comments to you, they were for those who seem to think that the conjugate circuit is perfect in its response to the emf from the voice coil motion. I for one have chosen to use only under-hung voice coils in my speaker design and can assure you that the inductance is linear in my design. But that does not mean that it still doesn't have any changes caused by voice coil heating with added power, that is just a given with any increase in power. I also have Esa's book at hand.
What I do like about the concept as proposed by the cover of his book is including the moving coil in the feedback loop, that to me is the most relevant aspect to improving the loudspeaker amplifier interaction, baring whether we are talking CFA or VFA as the driving force. I have moved in the direction of direct connection of amp to speaker with all network components before the amplifier. except for that damned cap needed for dc blocking on a tweeter I can see no reason to have any component in between the amp and speaker myself. I am thinking that a push pull application of amplifiers would also be an improvement over the simple single ended amplifier situation that is most prevalent but then we have a second amplifier and a balanced drive so we are into another conversation.
I have made no comment on whether the proposed network as Joe has worked out sounds better or not, I do not have an opinion on that and would need to hear it to make any comment.
Jan, you've just stated Ohm's Law (V=IR) extended to complex impedances:
V=IZ
You really didn't need to sim a capacitor in parallel with a resistor to prove that.
I think this is right. Conjugates assume linearity in the driver, which is not a gimme. But maybe better than nothing. I do remember Steen Duelund published a "better" Zobel network for a speaker's inductance correction than the usual RC. I really musn't waste time on it tonight, too much to do, but I will look it up.
Jan, you've just stated Ohm's Law (V=IR) extended to complex impedances
You really didn't need to sim a capacitor in parallel with a resistor to prove that.
Yes I did. You and Joe still deny this, so all I can do is explain it hoping your nickel will drop.
Jan
I appreciate that. I wasn't trying to have a go at you, but I did have a point of difference to explain, or at least I felt so.
I would love somebody to review Esa's book, to get a different but hopefully fair and objective take on it.
Having Esa's book, I have a thought for you, actually a question, and in view of the ideal 'tank circuit' can totally flatten the impedance (quite simple when the box is sealed), and the FR below 100 Hertz becomes totally immune to the source impedance of the amplifier, the FR is LOCKED IN, then what role does 'damping factor' have?
I think it reveals something very interesting.
Over to you.
Straw man, please come in?
Please Jan. No more character assassinations, I can only die so many times.
Show where I denied that. And I don't think Steve has either. I would not mis-characterise your stance, only argue against it IF I did not agree.
You may actually be surprised that there are many things I would agree with you on, some fully, some partially, but where does this crusading come from, too aggressive for my liking. I don't feel the need to crusade, just learning and exploiting the universe I find myself in. This having to agree 100% of the time, I don't get it.
I would never bully others to my point of view.
And a discussion we should be allowed to freely air our thoughts without the constant "prove it" mantra. Good things come to those who wait, and that gives us time to discuss, weigh matters, ideas flow, possible explanations explored... it's called brainstorming.
And fun!
I should create an Avatar next to my name "Brainstorming Not Allowed."
I do too. Spent some time with him in the early eighties in Copenhagen - I think it was in the part called Frederiksberg, would love somebody to confirm that - such a long time ago. He was out there, more than me. But would the world not be a lot less if we were not allowed to go a little crazy every now and then, and pull back from the brink just in time?
Please do, I would love to see it. I avoid using RC or Zobels right across the driver terminals. It's tricky, but you have to resist the urge because it looks so good and yet may not sound so good. Life is full of temptations, alas.
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