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"Things that cannot be measured"

No one that sees a painting or photograph or movie or even holography or VR goggles will ever think they are there. Not sure why this belongs under "measurements".

And to be honest, the last thing I want to do at home is recreate the live music experience. Sure there's some excitement about the social occasion, but as a rule the sound quality is much worse, and the people are loud, etc etc. Spare me that stuff at home. There are preciously few "live albums" I'd listen to rather than the studio version. As a rule, the recorded studio album is far more balanced in every respect.
 
No one that sees a painting or photograph or movie or even holography or VR goggles will ever think they are there. Not sure why this belongs under "measurements".

And to be honest, the last thing I want to do at home is recreate the live music experience. Sure there's some excitement about the social occasion, but as a rule the sound quality is much worse, and the people are loud, etc etc. Spare me that stuff at home. There are preciously few "live albums" I'd listen to rather than the studio version. As a rule, the recorded studio album is far more balanced in every respect.

Not necessarily "live" albums. Live un-amplified music in an acoustically good venue. Virtually impossible to reproduce at home, but worth the time spent going out. Uncompressed dynamic music at its best.
I do like certain "live" albums - Jazz at the Pawnshop or Allman Brothers Fillmore East version of Memory of Elizabeth Reed is my favorite.
Since the mastering process always changes things - first and foremost compression - it is more a question of liking versus accuracy.
 
Not necessarily "live" albums. Live un-amplified music in an acoustically good venue. Virtually impossible to reproduce at home, but worth the time spent going out. Uncompressed dynamic music at its best.
I do like certain "live" albums - Jazz at the Pawnshop or Allman Brothers Fillmore East version of Memory of Elizabeth Reed is my favorite.
Since the mastering process always changes things - first and foremost compression - it is more a question of liking versus accuracy.
There still are albums that are recorded in a great studio or venue, without individual tracks for the different instruments being mixed together. But I prefer a live crowd is left our of it. Rare exceptions like Bill Evans' legendary Waltz for Debbie or George Benson's Weekend in LA excepted. As a rule I much prefer well recorded studio versions. And indeed prefer a well recorded studio performance to an artifical mix of different instruments.
 
Thanks for replying.

My understanding is that objectively "flat" in-room response is generally perceived as "bright", rather than "neutral".



I agree with this.
If the source material has bright sounding content, that that will come through with fidelity in a flat, neutral room/sound system.
 
I agree.



Do you think it's possible that a tone control could make a correction towards greater neutrality, such as in a situation where the speaker/room/listening position combination results in reduced SPL in the bass region? In this case, would it be accurate to describe the tone control's contribution in bringing up the bass region as "distortion"? (I don't think so; I think it would be "corrective equalization".)

What about a situation where the recording itself seems to be lacking in low-end energy; is it possible that a tone control could make a worthwhile beneficial contribution in this case? (Again, imo this would be "corrective equalization", not "distortion".)
Probably, but that neutrality would be only in ear of the beholder doing the adjustment.
 
There are still one (stereo)mic recordings being made.... in one take. They can sound great indeed.

For instance (when you like this type of music)



There is a player on this page that lets you hear all their albums completely.
+1; The latest in that series is their best yet;
down-to-the-downtown-tim-langedijk-paul-berner-logo.jpg
Down To The Downtown
"It’s music distilled to its essence, created with minimal means an embodiment of excellence through restraint. And the sound…..recorded by sound wizard Frans de Rond with just one 3-capsule stereo microphone, ensuring that the purity and clarity of these two master musicians' music resonates deeply with the listener. A recording with full phase coherence, perfect imaging, a wide and deep soundstage, and superior realism."
 
I propose to familiarize yourself with and discuss the following method of testing amplifiers both at the development stage and finished amplifiers
 

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No one that sees a painting or photograph or movie or even holography or VR goggles will ever think they are there. Not sure why this belongs under "measurements".

And to be honest, the last thing I want to do at home is recreate the live music experience. Sure there's some excitement about the social occasion, but as a rule the sound quality is much worse, and the people are loud, etc etc. Spare me that stuff at home. There are preciously few "live albums" I'd listen to rather than the studio version. As a rule, the recorded studio album is far more balanced in every respect.
But with studio recordings, you miss all those carefully timed coughs in the quiet spots.
 
But with studio recordings, you miss all those carefully timed coughs in the quiet spots.
The studio recorded album also misses the immediate interaction between musicians. In recorded studio albums, the guitar solo in the middle of the piece is some times played by a guy who is not even part of the band and added to the mix 6 months later.
 
I propose to familiarize yourself with and discuss the following method of testing amplifiers both at the development stage and finished amplifiers
There's a lot of misinformation in there.

SID has been solved for decades.
"In [8], the causes of SID were analyzed and it was concluded that one of the reasons for their
occurrence is excessive depth of NFB and its insufficient performance." This paper has been debunked over and over, its wrong.
"An analysis of information was carried out on amplifiers without NFB from such companies..."
There is no such thing as a commercial Amp without NFB."
"Despite the relatively high level of distortion compared to deep-NFB amplifiers, it is these
amplifiers that provide the best sound quality. And it is not surprising, because the signal delay in such
amplifiers is negligible"
Best sound quality according to who? At what point is the delay "negligible". And NFB does not delay a signal.

A test method developed on misinformation may not give meaningful measurements.
If your going to bash NFB get your facts straight.
 
This might be silly point, but sometimes I was thinking the different tasteod FR settings by person to person maybe from the different shape of their ears...sorry....
 

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Let's look at the application of the compensation testing method in practice. We see that only bursts allow us to identify additional types of distortion. And on stationary signals, both tests show the same result.
 

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That's what we use square waves for.
Well... at least during development as IRL there are no such sharp signals unless something is clipping in the analog signal.
TIM is well understood and is not something that can not be measured.
 
That's what we use square waves for.
Well... at least during development as IRL there are no such sharp signals unless something is clipping in the analog signal.
TIM is well understood and is not something that can not be measured.
Square waves are used to measure the rate of rise (SR) of the output voltage. There is no TIM distortion in this amplifier.
It is the compensation test using bursts that allows us to identify all types of distortions, including nonlinear distortions that we measure in the form of THD in %
 
TIM-distortion occurs when the slew rate is insufficient
 

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TIM-distortion occurs when the slew rate is insufficient
Before you dig deeper into stuff that was shown incorrect nearly half a century ago, you need to read and understand the analyses by Bob Cordell and Doug Self. It will make clearer why this is a non-issue in engineered circuits.
 
Before you dig deeper into stuff that was shown incorrect nearly half a century ago, you need to read and understand the analyses by Bob Cordell and Doug Self. It will make clearer why this is a non-issue in engineered circuits.
I hope you read both authors and what did you understand?
 
It means that you can detect that during the design stage and the simplest solution is to add an input filter that ensures such high dV/dt can not occur and the feedback loop will therefore never clip.
Also it helps if the output devices are faster which in the good old days was indeed an issue.

TIM is a known and well understood phenomenon and not the culprit of the 'we can't measure it yet' debate because it is measurable, simulatable, predictable, repeatable.

Lots of components, much overall feedback and high frequencies (way above the audible range) is something the designer has to deal with.

In the prototyping stage some measurements using square-waves under actual load and some probing in the amp is usually enough to detect instabilities and speed issues.
 
TIM-distortion occurs when the slew rate is insufficient
Which has been solved for 30 years. Your Sim is using impossible signals to show SID that dosnt actualy occur. And Im not sure you know what memory distortion is. A Sim won't show it unless its changing the temperature of components as it runs, no Sim I know does that.
 
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