Global Feedback - A huge benefit for audio

You need to be a bit more specific. If you do a well-designed and executed DBT to establish whether you can hear a difference between two amps, the result is objective fact. Nothing subjective about it.

Jan


Seriously?? So the subjective experience of 'yes, I can hear a difference here' and that's done in a DBT and there's nothing subjective about it?? The statement strains credulity.
 
Not at all, it is exactly the way it is. Consider. You do say 100 runs, each time asking people whether they are listening to A or B, with A and B secretly, double blind, selected according to all the applicable rules for a DBT - I don't think we need to go into that at this point.

Then you tabulate the result, do the usual statistical processing and come to the conclusion: there is a 92% probability that people can indeed hear a difference between A and B. That is an objective, scientific result.

It is very well possible to do an objective, scientific study based on subjective experiences. Marketing people do it all the time, and make big bucks precisely because the result is objective and thus has predictive power.

Jan
 
Not at all. Lots of very smart people (I spent 20 years working with PhD solid state physicists) are just misguided sometimes. That’s human.

Which all goes to reinforce what I was taught doing my MBA: knowledge is very sticky and does not transfer easily between different fields of study - which BTW is why multi- domain problems are called ‘wicked’ problems.

I would not presume for one minute for example to be able to comment authoritatively on matters relating to medical science (let alone electronics 😉 )

Thank you for your attitude, Bonsai. Myself, I am a PhD doing biomed research. Audio is just lifetime hobby.
I had No experience before on diyaudio people slinging mud at each other.
 
Why not discuss something more interesting ?
How about how to design a feedback control loop of say 100kHz bandwidth that includes the speaker chassis ?

That is surely a lot more fun than arguing over a century old topics of NFB in amplifiers, not ?


I'm with Patrick. Since this thread was woken up for a bit of stirring by one person its just repeated arguments 40+ years old.
 
Seriously?? So the subjective experience of 'yes, I can hear a difference here' and that's done in a DBT and there's nothing subjective about it?? The statement strains credulity.
I mean this says everything. The usual suspects here are so seriously confused, they don't even understand what basic terms mean, or deliberately act confused to try to attract sympathy while attacking the next straw man argument..

And this is not directed at you in particular, but when you can observe people starting to deny reality, to forfeit into completely solipsistic ideologies, just so that they can "save" their absurd views, you know it's over.
Just like you know it's over when you play hangman and on the piece of paper you not only see a man drawn hanging from the gallows but the whole townsfolk gathered around him with a castle in the background.
 
Last edited:
Why not discuss something more interesting ?
How about how to design a feedback control loop of say 100kHz bandwidth that includes the speaker chassis ?

That is surely a lot more fun than arguing over a century old topics of NFB in amplifiers, not ?

😉


Cheers,
Patrick

Active noise cancellation systems in the room have been tested. Multiple speakers, microphone and DSP.They work poorly so far. Especially at low frequencies 🙁
Headphones are better.
 
Not at all, it is exactly the way it is. Consider. You do say 100 runs, each time asking people whether they are listening to A or B, with A and B secretly, double blind, selected according to all the applicable rules for a DBT - I don't think we need to go into that at this point.

Then you tabulate the result, do the usual statistical processing and come to the conclusion: there is a 92% probability that people can indeed hear a difference between A and B. That is an objective, scientific result.

It is very well possible to do an objective, scientific study based on subjective experiences. Marketing people do it all the time, and make big bucks precisely because the result is objective and thus has predictive power.

Jan


We're talking past each other here- I'm not disagreeing with you; I still stand by 'the subjective experience does in fact still hold water in engineering and science.' -Which what you were reacting to. This seems more like semantics.


I am sorry, I was out of line, apologies. But seriously, suggesting that listening doesn't need a brain, I couldn't believe I read that!

Jan


Neither could I. I've read a lot of studies on hearing perception issues, and one thing you find out about rather quickly is the existence of tipping points employed by the brain.
 
I mean this says everything. The usual suspects here are so seriously confused, they don't even understand what basic terms mean, or deliberately act confused to try to attract sympathy while attacking the next straw man argument..


I found this to be ironic: At first I thought this was aimed at me, but I found myself agreeing with it entirely. So I'm 'seriously confused' about that 🙂 not that it matters. IOW this statement can be interpreted subjectively several ways 🙂
 
I'm with Patrick. Since this thread was woken up for a bit of stirring by one person its just repeated arguments 40+ years old.

It has been flogged to death. But atmasphere gave us a link to Floyd Toole's work which wasn't available 40 years ago. His investigations are a good point for sober reflections on certain things. I.e. the competence of reviewers and two examples where high end (horrible term) doesn't cut it.

One can also infer that Toole does not think class D amps are detrimental. So the question is, are people going to accept the findings or declare it as bunkum?
 
Yes indeed. Taking a cue from Toole who observes meaningless specs from speaker manufacturers, I believe the parameters by which we judge amps are too narrow. Meaning that significant aspects of performance remain hidden. We are bound too closely to the 20Hz - 20KHz 'thing'.