@Bwaslo:I really must work out everyones names. You are Bill. I will remember that now. I know I also need to work out who is Brad....
It often takes a case to get shrinks to talk, Bill-Bill.
(though I've heard from a reliable source that they sometimes go pro-bono on eachother's couch)
(though I've heard from a reliable source that they sometimes go pro-bono on eachother's couch)
Define your understanding of "easy" (in this context), and support it with a credible proof.
No, it is not.
Just when I was about to believe the GEB conceded the CFA has no advantage over VFA (in audio, of course).
About professionalism Vs amateurism I think their is no way to use this criteria as a reference of talent. By example, when I was working in my R&D department, this was the period when I had the least original ideas. Because we are overloaded with daily work and too tired and sometimes bored to dream or even think "out of the box".
But, on the other side, it can be a reference of competancy: managers do not hire people without first checking their competencies.
But, on the other side, it can be a reference of competancy: managers do not hire people without first checking their competencies.
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The guy who is ignorant of the similarity between mixing a recording of a live event and putting together a studio recording. Live events are often technically far more challenging for a number of reasons.
That just tells me what I already know, which is that you don't understand that in either case the process is pretty well defined to be what it is and the same thing, and can't be separated into amateur and professional events.
The amateur and pro go through the same steps, and may even use the same equipment.
I got paid for my efforts, so that makes me a pro. ;-)
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Yes they are (easy). Bring a simple cap between output (for the load of this cap not being a problem for the output stage, increasing distortion at HF)) right to the base of the driver, and chose its value for limit of a flat bandwidth, and you got every time a perfectly stable CFA. Now, limit the bandwidth of the input signal by a low pass filter set in order to just avoid any overshoot with little square waves: you're done. With a comfortable phase margin.
And this for an easy to understand reason: not this added pole by the VFA negative phase transistor in the feedback path.
Instead of endlessly commenting (on a negative way) about CFA, that obviously, you don't know, please, learn how they behave, building at least one and listening to it. But I agree it can be dangerous, you could change your mind ;-)
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OK, since dissembling seems to now be your thing Bill, do try to claim that this collection of spew isn't targeting me.
Silly me, I seem remember when on another forum you seemed to be a decent human being, or was that just my prejudices?
Esperado, you have the right experience with VFA vs CFA vs D. That is where we are at today, as well. We even try D amps for full range, and they are getting better.
Does not make any sense, as usual. Please explain, if you want to be taken seriously.
Or not.
Waly, with respect to CFA's, as we discussed on the original thread, some of the HF poles lie below 0dB (i.e. above the ULGF) and the phase margin as a consequence is quite large. You need very little lag comp to make the system stable. This is one of the reasons also why you have wider loop gain bandwidths in CFA's - which some designers prefer.
In VFA' generally, more HF poles fall above 0dB (i.e. below the ULGF) and the phase margins as a result are not as large. You either have to pole split - the classic text book way to do it - or you need to resort to more advanced comp techniques, many of which have been discussed on the forum, or covered by Cordell, Self et al.
It is not an issue about which is better - both topologies have their advantages. Its about using what you are comfortable with. And if a designer prefers wide OLG BW and high slew rates, then so be it.
I personally think classic low OLG CFA's are easier to comp - that's my experience and I've built both VFA's and CFA's.
But, to get back to more mundane matters, can you do us all a favor and stop trolling?
In VFA' generally, more HF poles fall above 0dB (i.e. below the ULGF) and the phase margins as a result are not as large. You either have to pole split - the classic text book way to do it - or you need to resort to more advanced comp techniques, many of which have been discussed on the forum, or covered by Cordell, Self et al.
It is not an issue about which is better - both topologies have their advantages. Its about using what you are comfortable with. And if a designer prefers wide OLG BW and high slew rates, then so be it.
I personally think classic low OLG CFA's are easier to comp - that's my experience and I've built both VFA's and CFA's.
But, to get back to more mundane matters, can you do us all a favor and stop trolling?
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billshurv,
No sir we have not been introduced formally. I have just counted you as one of the British gentleman on this thread. I'm just one of those Yanks!
Steven
No sir we have not been introduced formally. I have just counted you as one of the British gentleman on this thread. I'm just one of those Yanks!
Steven
You repeated the same "explanation" (with the poles position) many times, this doesn't make it more relevant when it comes to the available phase margin (or loop gain). Sadly, I suspect you know that, and the proof based on maximum available feedback in minimum phase systems. This probably needs to be shouted, to penetrate some thick skulls:
In a minimum phase system, phase is not an independent variable. For a fixed compensation order, no extra loop gain can be obtained without a phase margin penalty. No extra phase margin can be obtained without a loop gain penalty.
Why you and others keep beating this dead horse, and purporting the same false technical arguments, is beyond my understanding, I suppose it must be a psychology thing, based on the need for the self-actualization in the Maslow hierarchy. Unfortunately, as much as some love to believe, "experience" does not replace "knowledge".
In all truth, I should also probably stop sanctioning these false technical arguments, since there is obviously no way I could persuade anybody here to pick a good book on this topic (and bwaslo just recommended a great one), sharpen a pen and do some homework before opening again the pie hole. Ignorance can be funny, this one became sad.
Quand le sage montre la lune, le fou regarde le doigt...
This little thing with 3 legs is a transistor. In a VFA, the feedback signal has to pass through it before to be substracted to the original one at the output of the LTP.
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