Well,all i can say is that i wish you luck with singing power supplies that you are all making and calling them "HiFi" amplifiers....and beleive that they are providing real output from whats on input - which is not......keep this in mind.Once you give a chance to your self to make and hear real HiFi you will all come here and apologize for most of what you wrote.
I started this thread to say that thinking out of the box is still possible even with all whats in books and to motivate R&D to go deeper.Saying that negative feedback is the key simply means that true understanding of power amplification is missing in knowledge and nothing else....this is not bad.....its simplest concept and easyest of course....and it makes money.Making of what i described is VERY hard but is the only way to have true output from whats on input and it makes so big difference in comparation with all whats available that its uncomparable.If i dont sell this as full project to some company you will be all invited to video demonstration (i know that video cant show real thing....but it will be close enough) once i decide to share with public what i made.
I didnt make this for money and thats why God let me to have it done.Just becouse i didnt make it for money i dont wish by any cost to make money of it.Most of you would do the oposite and all of you are doing oposite with what you are making......Wish you all the best in life and work!
Cheers,
I started this thread to say that thinking out of the box is still possible even with all whats in books and to motivate R&D to go deeper.Saying that negative feedback is the key simply means that true understanding of power amplification is missing in knowledge and nothing else....this is not bad.....its simplest concept and easyest of course....and it makes money.Making of what i described is VERY hard but is the only way to have true output from whats on input and it makes so big difference in comparation with all whats available that its uncomparable.If i dont sell this as full project to some company you will be all invited to video demonstration (i know that video cant show real thing....but it will be close enough) once i decide to share with public what i made.
I didnt make this for money and thats why God let me to have it done.Just becouse i didnt make it for money i dont wish by any cost to make money of it.Most of you would do the oposite and all of you are doing oposite with what you are making......Wish you all the best in life and work!
Cheers,
It seems like there's a lot of dogma and not much engineering associated with this claim.
It sounds familiar. I've seen this same "logic" applied to many different topics. This "logic" is usually applied by someone that knows far less than they think they know.
Dunning–Kruger effect - Wikipedia
It sounds familiar. I've seen this same "logic" applied to many different topics. This "logic" is usually applied by someone that knows far less than they think they know.
Dunning–Kruger effect - Wikipedia
Hi Mikelandjelo,
I think feedbackless class-D is acutally pretty easy to do, look at TI's digital PWM modulator DSP-s and the matching power stages, like TAS5548 + TAS5614A.
Interestingly these chipsets are quite unknown or underrated in HiFi/DIY circles, but according to some ears here, they sound as good or better
than the majority of the better built other technology amps.
These chipsets work without global feedback. Power stage TAS5614A has some undocumented internal compensation, probably for FET turn on/off timing. This can be considered as local feedback. But TI also have parts without it, which I never heard how they sound like.
I think feedbackless class-D is acutally pretty easy to do, look at TI's digital PWM modulator DSP-s and the matching power stages, like TAS5548 + TAS5614A.
Interestingly these chipsets are quite unknown or underrated in HiFi/DIY circles, but according to some ears here, they sound as good or better
than the majority of the better built other technology amps.
These chipsets work without global feedback. Power stage TAS5614A has some undocumented internal compensation, probably for FET turn on/off timing. This can be considered as local feedback. But TI also have parts without it, which I never heard how they sound like.
Hi Nigel,
check TAS5614A power stage data sheet. Due to the internal compensation it has
80 dB PSSR.
Furthermore it is a BTL design which lowers supply rail pumping.
PS: datasheet http://www.ti.com/lit/ds/symlink/tas5614a.pdf
check TAS5614A power stage data sheet. Due to the internal compensation it has
80 dB PSSR.
Furthermore it is a BTL design which lowers supply rail pumping.
PS: datasheet http://www.ti.com/lit/ds/symlink/tas5614a.pdf
The functional block diagram depicts a feedback loop of unknown order for each of the four output stages.
From the data sheet.
The problem with lying to engineers about engineering topics is that we can read the datasheet. We're not gullible consumers of the products. We design the products!
Nice try though.
Yes, I wrote this part has some unknown local feedback inside.
But who cares if the result is good, the PWM generation process is out of this feedback,
and on the design level you don't have to deal with analog problems from the speaker
port to the input of pwm gen. You can see it as fb less solution with good enough driver stage.
But who cares if the result is good, the PWM generation process is out of this feedback,
and on the design level you don't have to deal with analog problems from the speaker
port to the input of pwm gen. You can see it as fb less solution with good enough driver stage.
TI: Earlier they made open loop driver stages only. Then probably they realized that
with some compensation they can improve on timing of FETs and PSSR.
I would be surprised if that is a complex Nth order loop.
I think the point here is that they splitted the problem into PWM generation in digital domain, and making good enough driver stage. The former is limited only by the DSP and its clock source.
The later can be improved as FET technology improves.
with some compensation they can improve on timing of FETs and PSSR.
I would be surprised if that is a complex Nth order loop.
I think the point here is that they splitted the problem into PWM generation in digital domain, and making good enough driver stage. The former is limited only by the DSP and its clock source.
The later can be improved as FET technology improves.
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