Andy, this is nothing to do with PSpice or any other kind of spice for that matter. It's just one of the fundamentals of circuit design. Attempting to invoke transmission lines in four dimensional space doesn't change how a parallel loudspeaker crossover functions. It doesn't matter where those components are providing they are in the correct order. It is the same filter, functioning in the same way. The signal is AC. It does not flow in one direction only. The positive lead and any components that happen to exist in it is not 'more in the way' of the signal or driver than the negative. They are equally in the circuit all the time. That's how it works. Period.
Last year my cabinet building partner in crime & I actually did a pair of speakers for a client with the series filter components in the negative leg. I did it mostly to wind my mate Colin up, as he's not well versed in the subject & I wanted to show him this aspect of circuit design. To prove / demonstate, we also built an identical pair of filters (all components matched to within 2% tolerance) with the series components in the positive leg. Result: in accordance with physical reality. Zero difference in the measurements, zero difference in sound. Quod erat demonstrandum.
Last year my cabinet building partner in crime & I actually did a pair of speakers for a client with the series filter components in the negative leg. I did it mostly to wind my mate Colin up, as he's not well versed in the subject & I wanted to show him this aspect of circuit design. To prove / demonstate, we also built an identical pair of filters (all components matched to within 2% tolerance) with the series components in the positive leg. Result: in accordance with physical reality. Zero difference in the measurements, zero difference in sound. Quod erat demonstrandum.
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It's possible that one could not hear the difference. I was only speaking from a theoretical point of view since that is all I could do. I mean there are a lot of things you could do to your audio system but does not mean that it will automatically make an audible difference.
Just because something becomes a problem at 1MHz, does not mean it could not also be a problem at audio frequency.
Except for the minor point that all you have done is make a post containing a handful of fancy sounding but misapplied phrases from TL physics, an inaccurate claim about PSpice (ironic, given that nobody had mentioned it), and an incorrect understanding of the basic operation of parallel filters in an AC circuit. Your use of the word 'could' says it all. No. It really couldn't.
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PSpice is a 2D simulation. I can only simulate circuit at discrete points. To get a more accurate simulation, you have to use Maxwell 3D solver. The xover is basically a transmission line just like any cable is a transmission line.
In PSpice analysis, putting a component before or after does not affect the overall outcome. But in a 3D solver where every point in space is important, component order is very crucial. I mean PCB layout designers have found out long time ago (not sure why you haven't up to speed). For a given circuit, one layout might work but another layout might not work. This is common knowledge. I should not be bothered with it but I guess some people still don't understand.
No
They are accounted for.
George
By the way it's not the same as a Maxwell full 3D solver. You just replace the transmission line with an equivalent l-r-c ladder. It might come close but no cigar.
Why are you talking about PSpice Andy? You were the one who raised it, and nobody else has mentioned it, other than pointing out your incorrect statements about it. Moreover, no competent crossover designer would use it to design a filter since loudspeaker designers need to account for the summed electrical & acoustical response, not just the electrical, so its relevance is somewhere south of zero as far as loudspeaker crossovers are concerned. One might, if one was feeling less than generous, suggest you are trying to deflect attention from your fallacies. We are not dealing with a mysterious matter here, but a very basic aspect of electrical filter design that has been well understood for more than a century.
You have invoked Maxwell. I'm delighted you have, since many people here are well versed on the subject, and I have a long-standing interest myself. I note you have carefully avoided addressing any of the points made, most pertinently being your evidence that series components in one section of an AC circuit are less part of that circuit than if they were placed in another section. Please provide the EM derived equations supporting this claim.
You have invoked Maxwell. I'm delighted you have, since many people here are well versed on the subject, and I have a long-standing interest myself. I note you have carefully avoided addressing any of the points made, most pertinently being your evidence that series components in one section of an AC circuit are less part of that circuit than if they were placed in another section. Please provide the EM derived equations supporting this claim.
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Loudspeaker simulation uses a combination of Spice simulation or however terminology you use but just a variance of Spice, and an acoustic equivalent output. Basically, the .frd file provides an acoustic output and impedance of the driver for a given electrical input. The Spice simulation will provide you the resulting electrical input (given the topology of xover) then from there it figures out what is the acoustical output. I understand it's not 100% Spice, but it uses Spice (or something equivalent but the same) to figure out what is the voltage at the terminal of the drivers.
If you feel like I tried to deflect to hide my fallacies, then please point out specifically. To many of your posts are just throwing out accusations without any specifics.
Like I said, electrically the "paracross" makes a difference but whether you can here it or not, it depends on a lot of things ... may be you have a 2D hearing?
So what you are saying is that PSpice software has existed for more than a century, and that all electrical filters, be they crossovers or the rather large variety of other analogue electrical filters that exist, have been developed using it.
Bollocks.
Again I ask you to provide your documented Maxwell-derived equations showing:
1/ How alternating current is not alternating
2/ How an AC circuit has a fixed 'beginning' and 'ending'
3/ How series components placed in one part of a parallel AC circuit are less a part of that circuit than if they happened to be somewhere else.
No more dodging. No more avoiding. Get on with it. The equations. And for good measure I'll add
4/ Your documentary evidence showing all analogue electrical filters without exception are or were developed in PSpice software or its derivatives.
Because of course it doesn't matter if it's a loudspeaker. Your claim that components that are placed in a different leg of a parallel circuit result in
different circuit / system behaviour to what would happen if they were placed elsewhere, is by definition universal, and would apply whatever the specific application. Examples, if you please, of these differences in behaviour. Properly documented and reported in accredited, peer-reviewed research journals.
Bollocks.
Again I ask you to provide your documented Maxwell-derived equations showing:
1/ How alternating current is not alternating
2/ How an AC circuit has a fixed 'beginning' and 'ending'
3/ How series components placed in one part of a parallel AC circuit are less a part of that circuit than if they happened to be somewhere else.
No more dodging. No more avoiding. Get on with it. The equations. And for good measure I'll add
4/ Your documentary evidence showing all analogue electrical filters without exception are or were developed in PSpice software or its derivatives.
Because of course it doesn't matter if it's a loudspeaker. Your claim that components that are placed in a different leg of a parallel circuit result in
different circuit / system behaviour to what would happen if they were placed elsewhere, is by definition universal, and would apply whatever the specific application. Examples, if you please, of these differences in behaviour. Properly documented and reported in accredited, peer-reviewed research journals.
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Until you realize that Spice is 2D, Maxwell is 3D, then I am not sure how I can convince you.
You appear to be the only one talking about Spice. Nobody else is. The rest of us are talking about circuits and their operating behaviour & physics, not software which came along decades after the (rather elementary) physics was well-established.
So, you're not going to provide us all with your documentary evidence and Maxwell derived equations Andy. Now, I wonder why that might be... oh yes, of course. Because you're either trolling, or technically inept. Possibly both.
So, you're not going to provide us all with your documentary evidence and Maxwell derived equations Andy. Now, I wonder why that might be... oh yes, of course. Because you're either trolling, or technically inept. Possibly both.
Another accusation. I think I start doing what people here doing. Throwing out accusations for fun.
Edit: I supposed you're very good at it. The first sign of an angry man is throwing out these kinds of
accusations. Should we all start learning these kind of behaviors? Calling name?
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OK, I figure out how to explain to those who still stuck in 2D. I won't give the whole answer and you have to figure a bit by yourself. Since you still don't know Xsim is Spice base so I can't say I am too optimistic. But a bit busy at work right now ... maybe later.
Who is talking about XSim? I'm not. Nor is anybody talking about Spice. You are the only person constantly referring to software Andy: nobody else is. What we are talking about are the fundamental underlying physics behind a parallel circuit, all of which was rather well known before electronic computers even existed (and were in fact instrumental to their development). So let us hear no more from you about irrelevant software. Instead, let us hear you explain, with proven, referenceable physics, how alternating current is not in fact alternating, and how series components in one part of a circuit are less in the way of the signal than if they were located elsewhere.
OK, I won't mention software. Only hardware. But you could accept defeat now or face the truth later on.
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