Very well, but some quibbles: minimum phase can apply to nonlinear systems as well. The only requirement is that the phase be the derivative of the amplitude response wrt to frequency. And single valued functions indeed contain no loops, but if (for example) you have a 2d function unwinding in a 3d space, you can inadvertently have multiple values which are not loops in the 2d representation. Rooms have 3 dimensions (assuming the room size is time invariant!), the signal applied to them has one dimension plus time. So, no minimum phase (there's delays from reflections) and multiply valued (amplitude varies over space as well as time).
Since the concept of "Minimum phase" (MP) comes from "linear systems theory" it is dangerous to try and apply it to a nonlinear system. It may appear to be MP at one level and not at another one - so is it or is it not MP? It cannot be defined.
Also MP is a one dimensional concept and has no multidimensional meaning. A room can be MP from a source to one point and not be to a different point - again it cannot be defined.
I'm sorry Guru Wave. I'm just trying to add to my knowledge & experience from my own poor attempts at these techniques of which you are expert. 😡I thought you understand the difference between damping of ringing and equalizing the rest of response that can't be tamed mechanically?
But I'm confused 😕 You say
- You've tried the 0R1 resistor, PFB bla bla method
- unlike other people, you find no distortion advantage
- There is a need to make sure Impedance of speaker is flat
- But no need to compensate for the bass resonance in a speaker which is surely the biggest feature in a speaker's impedance
- That Audyssey solves everything
- Audyssey DOESN'T solve everything
Do you see less ringing with the PFB? Is this acoustic or electrical? Is it at LF?
Messrs George & SY, I'll pontificate a little about Minimum Phase later cos I'm a pseudo guru on the subject .. especially as it pertains to speakers & rooms.
You too ?cos I'm a pseudo guru on the subject
Did-you suffer slings and arrows ?
[edit] My English humor is pathetic.
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You too ?
Did-you suffer slings and arrows ?
It is hard to tell what he suffered, but as the result he definitely acts as if he sees contests in any discussion.
Hard ? Mr kgrlee is the patient, not the disease.It is hard to tell what he suffered
Hard ? Mr kgrlee is the patient, not the disease.
Darn. I was hoping to use the phrase "your a disease, I'm the cure"
jn
Darn. I was hoping to use the phrase "your a disease, I'm the cure"
It is called Symbiosis 🙂
My favorite example. These signals differ only in phase of one of the spectral components. For absolutely identical amplitude spectra, we get totally different time domain signals. One of them will push the amp to clipping, the 2nd will not ..... 😎
One has to be careful when working with amplitude spectra only. It is only a half of the necessary information.
One has to be careful when working with amplitude spectra only. It is only a half of the necessary information.
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It is called Symbiosis 🙂
No. It's called Cobra, as in Cobretti.
jn


I believe he was responding to your posting verbage with sarcasm. I must admit that what you wrote could be read several ways.
It would be nice if you both stood down. I enjoy tremendously the technical content you both provide, and wish it to remain above animosity.
thanks,
jn
I believe he was responding to your posting verbage with sarcasm. I must admit that what you wrote could be read several ways.
Any sentence can be read several ways, when out of context. Then sarcasm applied to the distorted meaning. The question is, why somebody would want to do that. Hence, my question, "What's your point?"
Any sentence can be read several ways, when out of context. Then sarcasm applied to the distorted meaning. The question is, why somebody would want to do that. Hence, my question, "What's your point?"
I was trying very subtly to make a point. Too subtly I see.
You were condescending, he responded with sarcasm.
Again I ask. Please stand down.
j
Again I ask. Please stand down.
I respect your desire, but I still want to know, what's his point. I am curious. 😉
Protons are boring, electrons excited and annoying, neutrons are elegant.
1 part positrons
1 part antiprotons
Mix gently (stirred, not shaken)
Turn off the octupole field.
run..
j
This is my testament: I legate my soldering iron to my mother in law.......Turn off the octupole field. run..
.....
....
So that we are clear, I know and you know what the behavior will
be, but the neophytes who lurk here deserve to be clued in. And I was
perfectly serious - I am interested whether the simulations will show the
parasitic oscillation.
😎
For the neo-s reading and wanted to start into SIM -- The low cost sims dont take into account anything that isnt on the schematic. They dont know that you built the circuit with long lead lengths to the gate or have any capacitince to the heat-sink-ground... power supply inductance or C bypassing lead lengths. Nor pcb strays, field couplings etc.
So, no they wont predict oscillations except those caused only by the part values, part models on the schematic and topology. And, then only if the models are sufficiently complete and accurate. And, for semiconductors, that seems to be a big IF.
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does that mean some here conceed there are non-"neo-s" using sim? - that would be a refreshing, adult change...
Hey, Anitoliy, go easy on poor Richard, 🙂! He's an Aussie, we have a very free and easy way with our humour, and it can easily be misinterpreted by others: he's meaning no malice -- just like you, trying to reach a common understanding ...Any sentence can be read several ways, when out of context. Then sarcasm applied to the distorted meaning. The question is, why somebody would want to do that. Hence, my question, "What's your point?"
So, please, on bended knee I implore you to forgive the poor fellow ... 😉
Frank
does that mean some here conceed there are non-"neo-s" using sim? - that would be a refreshing, adult change...
Shame on me, I don't use sim. I used some to draw pretty looking schematics. Now I draw schematics in PCB design software. Probably if SIM would be combined with PCB design software it would consider parasitics, but I never heard of such software.
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