Your subjective description points to CFA improved VLF noise behaviour.
The VFA effective NFB path incorporates two more transistors to add 1/f noise.
Dan.
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Exists some comparative measurements (not only race for SR, but distortions spectra for various levels and frequencies, PSRR-mains background and intermodulation products, noise and others) of those different approaches (VFA/CFA with the same VAS and output stage)? I saw no measurements. Or conclusions about CFA superiority for audio power amplifier are stated only on basis of subjective (biased )testing and simulations?
I think this "junk" (electronic) is made for exact reproduction, not for pleasure. Pleasure should be the music itself, as is, it must be contained .
I think this "junk" (electronic) is made for exact reproduction, not for pleasure. Pleasure should be the music itself, as is, it must be contained .
Not true for my conditions... turbo charging the engine. A carb will flow a lot more air thru it if when connected to draw-thru a turbo. Just the cal is all off if you do. I had run the whole engine just fine on a single 45dcoe opened way up and recal'ed internally, up to 12 psi.
With very low distortion speakers, really clean HD Mastered music files, and listening in the near-field with minimal room interaction (doesnt everyone do this?) the VFA and CFA difference is pretty large.... sonically. That is in MHO, of course.
THx-RNMarsh
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I wouldn't do it that way, but the way I approach a boosted engine is tune the hell out the NA setup and when that is optimised, add boost. But that particular cat can be skinned in many many ways 🙂. I like getting the power at lower boost if I can.
The sickids here play simulation knife & sword fights all day long.
(the Dungeons & Dragons ruling superstar is currently seeing a therapist to learn to accept that he can't be no1 in everything. Has a photographic memory, boinked his first chick at age 15 and goes by the name Sex-Guru at his faculty, turned 21 yesterday)
I believe it was about the enjoyment of audio, and the way(s) of achieving divine sound.
Perhaps yours are, mine are blissfully linear
Probably so, but that's what decently judged loudness correction is for
I don't feel confused, perhaps your yorkshire pudding has gotten to you.
The way you describe it quality audio is total waste if time, effort and money, there's too much working against it all around. I do not share your sentiments.
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You are right on this...but... what about "noise" influence when you cannot hear-it even during silences from your listening point ?
That is my point of view too. But on details many people are not used to 'notice'.
Separation between instruments, both in the space and in the "wall of sound", very short details in the dynamic, this mysterious 'presence' that make you feel an instrument is in your room in 3D, like the subtle 3D effect with very little bokeh of some photographic lenses etc.
But, globally, distortion, balance, global dynamic is the same, don't you think ?
What i mean, is there is not so much a difference when you do a A/B immediate switch (blind or not). You need to listen alternatively to something like at least 10s of the same samples to figure out the differences. And to repeate severall time to can concentrate on the detail's differences involved. That what I called "Subtle".
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Real measurements are not so different. Ask OS, or Richard. Distortion's absolute values can change depending of the accuracy of your models, but only in absolute values, relative stay the same order. For everything else, simulations are good enough.
And both don't figure out real behavior with transients signals and with your real speaker load, anyway.
I believe those sims are good enough to explore the differences between the 2 topologies.
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Except CFA op-amps have poor current noise, do a survey of datasheets and CFA's will not come back as exemplary for 1/f.
This thread needs an "ignore car talk" button.
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Esperado ---- I agree that so far it is better but not greatly so. But consistent as always an improvement in the right direction. The new CFA power amp circuits done here is in a new league. I have a CFA model from Marantz (150W) and its qualities show same description you have given.
BUT Dadod's is in on a whole other level above it. It is easy to hear these life-like qualities now. It is just right and it is there for the fisrt time in my life. Others have heard my sample of it as well here in Asia with same results.
If the work by OS and others is like this CFA PA then, gentle men, we have a new ball game !!
THx-RNMarsh
BUT Dadod's is in on a whole other level above it. It is easy to hear these life-like qualities now. It is just right and it is there for the fisrt time in my life. Others have heard my sample of it as well here in Asia with same results.
If the work by OS and others is like this CFA PA then, gentle men, we have a new ball game !!
THx-RNMarsh
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Just before Scott activates the "ignore car talk" button.
It's not only high static pressure 🙂
George
It's not only high static pressure 🙂
George
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Composite power amp ?
(Please press 'ignore' now, and wait for further instructions)
For the record, I am not a CFA fanboy.
The long and torturous CFA vs. VFA thread that I kicked off certainly bears witness to that - I remained scrupulously neutral throughout. I've designed and built both types and listen to both regularly.
As I have said many times before, CFA topology amps are another string in my bow - I am glad I made the effort to understand and design with them, and hopefully encouraged a few others to do the same.
If someone trashes 'em, or claims they are inferior, I'll continue come out slugging.
I'll step away from this subject now - clearly its as emotive as ever . . . nothings going to change.
The long and torturous CFA vs. VFA thread that I kicked off certainly bears witness to that - I remained scrupulously neutral throughout. I've designed and built both types and listen to both regularly.
As I have said many times before, CFA topology amps are another string in my bow - I am glad I made the effort to understand and design with them, and hopefully encouraged a few others to do the same.
If someone trashes 'em, or claims they are inferior, I'll continue come out slugging.
I'll step away from this subject now - clearly its as emotive as ever . . . nothings going to change.
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