Thinking aloud: obj / sub / ABX cyclic arguments etc Part III

[hammeredklavier]

It isn't a problem. The waiting list for these DACs or the new version is measured in months if not years. This DAC would find a new home very quickly if I decided the Rega Apollo R that it sits next to was "transparent."

And you STILL don't want to discover whether you can really hear any difference? You must have too much money!

 

[Yank]

I agree with the first part, but I would also say it's for audiophiles who want to know what they really can hear and what they can't. That's why professionals use it, to determine audibility of certain phenomena, and to eliminate what's not relevant.

S.

Can you cite some of these "professionals" who are documented, proven users of double blind testing? I suspect it's actually very rare in consumer electronics, at least outside the axis of the Canadian National Research Council, and maybe Harman Intl.

I bet Behringer have never done it.

 

[Nic P]

I will repeat a post which I haven't posted for over a year.

I became regarded (God knows how) as an expert in "The Scientific Method". A number of learned journals asked me to review papers submitted that were based on the analysis of experimental data. Sadly I had to reject approx 90% of the papers because the experimental method was so flawed, or the analysis methods were so flawed, that the results were of no validity.

One of my best friends was in a similar position in the medical arena and used to complain that she had to reject over 95% of her papers.

Nic P

 

[mudlark]

I will repeat a post which I haven't posted for over a year.

I became regarded (God knows how) as an expert in "The Scientific Method". A number of learned journals asked me to review papers submitted that were based on the analysis of experimental data. Sadly I had to reject approx 90% of the papers because the experimental method was so flawed, or the analysis methods were so flawed, that the results were of no validity.

One of my best friends was in a similar position in the medical arena and used to complain that she had to reject over 95% of her papers.

Nic P

The Edwina Curry factor.

 

[Paul R]

The problem is that after the appearance fo the term objectivist and subjectivist (which are confused labels/insults) people have started to reverse engineer the word subjective and objective to take their meaning from the confused ideology words.

The words have generally agreed meanings outside of audio, trying to define them using examples of engineering usage is circular.

The BBC were evaluating subjective preferences not of individuals but of groups, they did this objectively. And the differences they were evaluating were objectively real. When Steven reports that his Rega has a soggy bass this is a purely subjective assessment. Confusing the two is very unhelpful.

I don't know why we cannot keep subjectivity where it belongs, in the mind of the observer, expressed as a personal experience that may or may not reflect the reality of one aspect of the object's performance and back story.

Paul

 

[Steven Toy]

The words have generally agreed meanings outside if audio, trying to define them using examples of engineering usage is circular.

The BBC were evaluating subjective preferences not of individuals but of groups, they did this objectively. And the differences they were evaluating were objectively real. When Steven reports that his Rega has a soggy bass this is a purely subjective assessment. Confusing the two is very unhelpful.

I don't know why we cannot keep subjectivity where it belongs, in the mind of the observer, expressed as a personal experience that may or may not reflect the reality of one aspect of the object's performance and back story.

Paul

I am cool with that. It should be in the AUP imho that subjective viewpoints that are explicitly stated as such should only be challenged with contradictory subjective viewpoints.

To qualify my statement regarding the Rega Apollo R's soggy bass, firstly it is an excellent transport, secondly in the context of a system of similarly-priced components it is still an excellent CD player/DAC.

 

[maxflinn]

Don't know - I am repeating the term and referring to the argument Robert used in this post:



I guess you need to ask him what he means by 'distorts'. I kept asking him to define the 'requirements for transparency' for a DAC, but he wouldn't. You may have better luck.

There's a thread here on which you can see that the designer of the MDAC is working rather hard to improve it. I think he might be a bit miffed at the suggestion that he is adding distortion. Not to mention Roberts other belief that a Dacmagic at half the price sounds as good!

How does Joe's definition sit with you?

Any change in the shape of an original waveform, apart from gain or attenuation

 

[mudlark]

I am cool with that. It should be in the AUP imho that subjective viewpoints should only e challenged with contradictory subjective viewpoints.

I don't think so. There are varying degrees of subjective lunacy. Those that are thrown in as if they are fact are always going to be open to challenge. To try to prevent this is not going to work. The other type that winds me up is "I can hear sound at 25kHz" and "I can hear a sparrow fart during the louder bits of the 1812 orchestra". You know, physically impossible.

 

[Tenson]

Not to mention Roberts other belief that a Dacmagic at half the price sounds as good!

It's not just Robs belief. If you remember I held a DAC bake-off some months ago? Everyone who came held the opinion that any differences between the MDAC, DacMagic or V-DAC were 'insignificant'.

 

[Nic P]

The Edwina Curry factor.

Don't really understand. Curry stated that a large percentage of egg production (aka chickens) was infected with salmonella. This was true, but she failed to mention the low percentage of transmission to eggs. However, if you handled a raw chicken and didn't wash your hands properly .... Nowadays most chickens are inoculated.

I really understand the scientific method and most of the posts on this thread are (how can I put this politely) not fully informed. It would be about as easy for me to educate the posters as it would be for a brain surgeon to instruct a butcher in their art.

Fools rush in where angels fear to tread.

Last post on this particular subject

Nic P

 

[Joe P]

Max,

How does Joe's definition sit with you?

Any change in the shape of an original waveform, apart from gain or attenuation

I should have gone a bit further to qualify that -- changes in the shape of the original waveform that can be quantified (which depends on the skill of the measurer and the measuring equipment) and changes in the shape of the original waveform that are perceptually relevant.

There's no practical difference between 0.001% and 0.0001% THD, despite the later being an order of magnitude lower, but there might be a big difference in 1% THD that's mostly 2nd order harmonics vs 3rd order or whatever.

Joe

 

[Nic P]

Max,


I should have gone a bit further to qualify that -- changes in the shape of the original waveform that can be quantified (which depends on the skill of the measurer and the measuring equipment) and changes in the shape of the original waveform that are perceptually relevant.

There's no practical difference between 0.001% and 0.0001% THD, despite the later being an order of magnitude lower, but there might be a big difference in 1% THD that's mostly 2nd order harmonics vs 3rd order or whatever.

Joe

Breaking the rule in my last post ... aaaaaaaaaaaaaaaaaaaahhhhHHHH!

None of you has a f******g clue what is important (and neither does anyone else). There is only a limited agreed understanding of the subject. It just isn't important enough to attract the megabucks to gain that understanding. Promise I will shut up now.

Nic P

 

[sergeauckland]

Can you cite some of these "professionals" who are documented, proven users of double blind testing? I suspect it's actually very rare in consumer electronics, at least outside the axis of the Canadian National Research Council, and maybe Harman Intl.

I bet Behringer have never done it.

Well I've done them.

S.

 

[mudlark]

Don't really understand. Curry stated that a large percentage of egg production (aka chickens) was infected with salmonella. This was true, but she failed to mention the low percentage of transmission to eggs. However, if you handled a raw chicken and didn't wash your hands properly .... Nowadays most chickens are inoculated.

I really understand the scientific method and most of the posts on this thread are (how can I put this politely) not fully informed. It would be about as easy for me to educate the posters as it would be for a brain surgeon to instruct a butcher in their art.

Fools rush in where angels fear to tread.

Last post on this particular subject

Nic P

What I meant was a "helpful" person taking half a conclusion and adding their own interpretation. I was concurring with your experience. My particular experience was the bse situation.

 

[sergeauckland]

Breaking the rule in my last post ... aaaaaaaaaaaaaaaaaaaahhhhHHHH!

None of you has a f******g clue what is important (and neither does anyone else). There is only a limited agreed understanding of the subject. It just isn't important enough to attract the megabucks to gain that understanding. Promise I will shut up now.

Nic P

Nic, whether you shut up or not, many people DO have a full understanding of what's important sonically, how to measure them, and how to distinguish between two items through the use of blind tests. Many enginers working in this field have been doing the testing for yonks. The BBC's Research Department at Kingswood Warren was one notable centre of such research. The Fraunhoffer Institute in Germany is another. Their development of Perceptual Codecs was centred on perceptual blind testing, as the quality of such codecs is measured by the "annoyance" factor they achieve, which is entirely based on blind listening panels and statistical analysis.

In the USA, RCA and CBS were both very active in audio reserach, and Dolby Labs in their UK research centre did some superb work on perception.

So to say that no-one has any idea about these things seems to me to be wrong.

S.

 

[Yank]

Well I've done them.

So by "professionals" you mean bench techs?

 

[Joe P]

Nic,

None of you has a f******g clue what is important (and neither does anyone else). There is only a limited agreed understanding of the subject. It just isn't important enough to attract the megabucks to gain that understanding. Promise I will shut up now.

It's true I don't have a clue, but I simply buy -- actually, bought * -- stuff I like the sound of, then I play records and CDs.

Joe

* I'm not looking to upgrade or switch any more. As far as I'm concerned, my hi-fi is journey complete. On to a musical journey now -- but not Journey. They suck ass.

 

[Nic P]

Nic, whether you shut up or not, many people DO have a full understanding of what's important sonically, how to measure them, and how to distinguish between two items through the use of blind tests. Many enginers working in this field have been doing the testing for yonks. The BBC's Research Department at Kingswood Warren was one notable centre of such research. The Fraunhoffer Institute in Germany is another. Their development of Perceptual Codecs was centred on perceptual blind testing, as the quality of such codecs is measured by the "annoyance" factor they achieve, which is entirely based on blind listening panels and statistical analysis.

In the USA, RCA and CBS were both very active in audio reserach, and Dolby Labs in their UK research centre did some superb work on perception.

So to say that no-one has any idea about these things seems to me to be wrong.

S.

Haven't reviewed it personally, so cannot comment. If you have and fully understand it, can you explain it to other posters without the necessary training? I was asked to explain to a customer what quantum computing was. I answered truthfully that without about 3 years postgraduate Maths/Physics training it was not possible.

The gulf between experts and laymen is absolutely vast. Occasionally a genius at communication can bridge this gulf, but I doubt we have many such people on pfm.

Nic P

PS Brian Cox ain't such a genius.

 

[maxflinn]

Max,


I should have gone a bit further to qualify that -- changes in the shape of the original waveform that can be quantified (which depends on the skill of the measurer and the measuring equipment) and changes in the shape of the original waveform that are perceptually relevant.

There's no practical difference between 0.001% and 0.0001% THD, despite the later being an order of magnitude lower, but there might be a big difference in 1% THD that's mostly 2nd order harmonics vs 3rd order or whatever.

Joe

That has complicated things slightly, Joe

Anyway, I was going to ask AndyU how the MDAC 2, for example, might have a different sound to the current, modded MDAC, if no distortion was introduced into the new model.

I'd suggest that assuming the current one is transparent, adding distortion is the only way of differentiating the two, as there's no such thing as more audibly transparent.

Therefore it's my understanding that using a graphic equalizer with the current MDAC (or any audibly transparent DAC) it would be possible to create the exact sound of the MDAC 2.

 

[sergeauckland]

So by "professionals" you mean bench techs?

I don't understand the term 'Bench Techs', But if you mean maintenance technicians, I would expect some may have done that sort of testing. I have never been a maintenance technician, so can't speak for them. Certainly I did blind tests when I was a young Development Engineer, as it was all part of the training in how to listen and what to listen for. I also did a lot of sighted testing, mostly involving measurements, as part of the design process. Listening tests whether sighted or blind as appropriate have been used for many years, especially as final 'reality checks' as part of the sign-off process of a new design, but also to establish audibility in things like perceptual codecs.

S