John Curl's Blowtorch preamplifier part III

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Is-it the result of a serious statistical study ?
If yes, I have learned something today and I thank-you for this.
Yep, if you look into the history of ITU-R 486 you will see it was originally developed by the BBC research dept in the 60s - Report EL-17, "The Assessment of Noise in Audio Frequency Circuits" to determine the audibility of noise in broadcasts. It led to CCIR-486 which was later adopted as an international standard ITU-486
So lots of evaluation/analysis & research went into - the same as the Fletcher-Munson curves which are loudness curve perception using single tone test signal & NOT complex tones
 
Just to tease a little more PMA, let-me try an other photographic image, staying in the "landscape" analogy.

Electrical measurements are like téléphoto lenses (with more or less AC), and listening like very large angles with all the geometrical aberrations, diffractions, light ghost reflexions that comes with.

Looking at the color balance, you can use a pure technical position and set your camera to, say: 6500°. You will most of the times constat your colors not convincing. You can choose inside-it several more or less grey ot white points, and ask you photoshop (or the same) to tune the color balance accordingly. You can have very different result on each of those points. You can even photography a neutral grey card, and use-it to make your application adjust the overall to the exact color balance of the light: you can find that, in some parts of your photo, colors are not accurate comparing with direct look at the same landscape. Too much blue in the shadows, by example.
Then you take the automatic as a base, and you slightly process to manually adjust the colors that seems unnatural. Bingo.

Same thing with the dynamic curve in the whites and the blacks, the local contrast etc.

Let me try an other comparison. In order to calibrate my screens for photography. I use a Spyder5 calibration device. It gives-me a lot better result than everything i can try manually. For two reasons: first I do not dispose access across the guy interface to of all the local fine tunings that allows Windows with a text file. Second, I f i see the defects, I'm blind to know exactly where they are and correctly address them in an exact opposite curve.
But, looking a the result of my calibration device, it is not perfect neither.
So, i use to make little manual adjustments to the near perfect work previously done by my calibration tool in order to approach more what I think is a neutral curve, both in color and light curve. Bingo.
 
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I just don't get the logic of smearing someone's posts by claiming the poster has commercial interests,
Not claim but a reminder to other readers who aren't yet familiar with certain posters. Have you ever heard of a phrase "fox guarding the hen"? To unsuspecting owner of hen, the fox's offer to guard for free would seem like a good deal. The owner should to be notified about the identity who that offer is coming from, unless he doesn't cherish his livestock.
even going so far as violating the rules by name-calling (shill, snake oil salesman).
If posting the words shill, snake oil salesman is in violation of forum rule, mod/s would have done something about it.
The smear-campaign seems to focus on members whose posts the smearer doesn't like, not all those with commercial interests.
Real smear campaign is coming from those with audio business interest against DBT.
 
With regard to this whole subjective vs objectivist thing.

In my book it’s quite acceptable to describe subjectively how something sounds. You put some opera on, the recording is great, the system is faithful (whatever your interpretation of that may be) and you go on an emotional journey.

The problem of course with this whole thing is when people try to ascribe their emotional experiences to technical aspects of the equipment and then open themselves up to ridicule by those who technically are highly proficient.

I am very comfortable describing my DIY amplifiers as sounding ‘liquid’ and ‘light and fast’ or ‘having an expansive sound stage’ because that’s what I experience when I put a record on and sit back to listen. That’s the soft, emotional stuff which is exactly what music and art brings out. But I draw the line for the most part at explains those experiences in engineering terms. Electrons feel nothing. Neither do transistors, or speaker cables or any other physical part of a Hi-Fi system.

And, whether people like it or not, visual cues play a seriously significant part in all of this. How many of you, after two or three glasses of wine at dinner in a nice restaurant have not looked across at you wife and thought ‘damn, you are beautiful’. It’s the same with Hi-Fi, but you can get that feeling without the alcohol. :D

The problem in all this arises when people coming from the subjective emotional side try to explain their experiences in electronic engineering terms.
Well put! But the emotion is so strong with some that none of what you pointed out gets through them. :(
 
All right, I have exaggerated a bit.
In my case, 6kHz is VHF. 9kHz is UHF and 11kHz is microwave.

No, only with pure tones by the audiologist.:wave:

George

There you go - not noise signals. You might be surprised with that result.

Noise is handled differently to tones as it is broadband & so excites multiple side-by-side critical bands of the auditory filter created by the cochlea.All sound is analyzed using this filter which splits sound into distinct frequency bands.

This model explains masking where one sound close in frequency to another can mask the sound of the other - if both sounds fall within the one ERB the louder one will mask the quieter one.

It also has significance with broadband sound like noise where side-by-side ERBs are excited & this results in an additive result, hence we are more sensitive to noise in the area centered around 6KHz frequency
 
Well put! But the emotion is so strong with some that none of what you pointed out gets through them. :(

Y’all just ain’t gettin it......

There’s something happening technically that I can make come and go from my system with just small changes....maybe emotional was the wrong term but it’s a response without an obvious trigger,
Nearest technical explanation I can find is ASMR.

It seems phase and timing related....how idk, but I believe it worthy to figure out for those in the industry.
 
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With regard to this whole subjective vs objectivist thing.

In my book it’s quite acceptable to describe subjectively how something sounds. You put some opera on, the recording is great, the system is faithful (whatever your interpretation of that may be) and you go on an emotional journey.

The problem of course with this whole thing is when people try to ascribe their emotional experiences to technical aspects of the equipment and then open themselves up to ridicule by those who technically are highly proficient.

I am very comfortable describing my DIY amplifiers as sounding ‘liquid’ and ‘light and fast’ or ‘having an expansive sound stage’ because that’s what I experience when I put a record on and sit back to listen. That’s the soft, emotional stuff which is exactly what music and art brings out. But I draw the line for the most part at explains those experiences in engineering terms. Electrons feel nothing. Neither do transistors, or speaker cables or any other physical part of a Hi-Fi system.

And, whether people like it or not, visual cues play a seriously significant part in all of this. How many of you, after two or three glasses of wine at dinner in a nice restaurant have not looked across at you wife and thought ‘damn, you are beautiful’. It’s the same with Hi-Fi, but you can get that feeling without the alcohol. :D

The problem in all this arises when people coming from the subjective emotional side try to explain their experiences in electronic engineering terms.

Sorry, it does not work. It’s like trying to explain to an atheist why praying makes one feel good. There’s no connection there.

And the same applies in reverse of course.

So, kick back, have a drink, enjoy your music but don’t try to explain why it makes you feel good because you’ve just replaced a 10 foot $5 mains cable you used to quickly lash up your speakers with $1000 Nordost’s.

:D
Agreed that subjectivists guesses at what they think might underlie their perception are just that guesses & not up to the usual approach demanded of engineering. However, the observation is not necessarily wrong because the underlying cause can't YET be explained in engineering terms. Science (as opposed to engineering) would never progress if this was the basis on which i toperated.

The other issue is that nothing wrong with your description of how you personally perceive your DIY amps, etc but if two commercial amps are being perceived as different sounding even though they are considered as indistinguishable based on measurements, then the trouble starts & it all kicks off.

It might be beneficial for all to just look at Scott Ws reception on ASR here when he made a post which was simply a benign comment about someone who finds the AHB2 amp is not relaxing & can't listen to it for long - prefers his NAD M22. The guy bemoaned that ASR " I won’t try to elaborate any further than that because aesthetic judgement are forbidden on this form" (forum)
Scottw simply posted "Is that true, it would be unfortunate if that was so?"

The backlash against ScottW's post is very typical of the type of yes "rabid objectivists" seen here & on many audio forums - afraid that any concession to subjective viewpoints will simply tear down their facade
 
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