Amir and Blind Testing

Great posts that say much in few words....

Amir and others on this thread are absolutely right: A/B comparisons are notoriously flawed by expectation bias; that’s just how our brains work. In my profession (drug discovery) we therefore use "double-blind" evaluations, where the experimenter (e.g. the audio dealer) and the patient (i.e. the customer) do not know whether they are receiving a new treatment, a standard treatment, or (in non-critical cases) a sugar pill (i.e. placebo). Only such an evaluation would either confirm or put in question Amir’s well-intended measurements, in the sense whether or not the data he measures are relevant to human musical enjoyment and thus would indicate - before you buy it - if a particular gear enhances or diminishes such pleasure (which is, I suppose, what this exercise should be all about). The respective measurements would indeed have to track with the "enjoyment score" after listening to a hidden piece of new gear or an old one, while the listener and the dealer would not even know what gear is being listened to. In that sense, Harry Pearson was correct in his criticism of both: lone reliance on measurements and on A/B comparisons. He also knew that a new piece of equipment might sound spectacular at the onset, only to become fatiguing after a few hours or even days, no matter how "good" the measured data were. Psychoacoustics were a budding discipline in his early days, and we are still just beginning to understand how we make esthetic decisions, and what important part THD plays in this puzzle, if any at all.

Psycho-acoustic is fundamental knowledge for tuning a room, physical acoustic is NOT ENOUGH, for example knowing the way our brain synthetize the information coming for our two ears from the two speakers and from the walls and the meaning of the delay in time between these two frontwaves and their timing reflections and the way we could use and timing them to differentiate each one of them for each ears... i used that to decide for an asymmetric distribution of my Helmholtz resonators from each speakers and around the room with succeess...

No need to A/B blind-testing here....Our ears biases or pleasure level internal meter in the recognition of the timbre and imaging experience and any other acoustical cue are our guide and are our ONLY teacher here...

Precisely what Amir want to erase i keep it : our ears biases history... He is like a children playing with tools without learning with his BODY....He does not know that science is multi-disciplinary...And measure in one field means not the same in another field... It is the reason why concepts are more important than mere numbers...

Obsession to confirm biases is not scientific inquiry... But using acquired biases could be a scientific tool ...

Amir appears believe we all suffer from expectation bias. One problem how does that explain when the expectation is for things to sound no better or worse but they don’t?

This part pertain to the "nocebo effect"... When you claim that there is no positive difference ever and could not be one... But like someone painting himself in a corner Amir did not know that at all.... 😁😊 He dont see the "beam" bias in his own eye...And he look for the bias straw in others eye...Comical...

Anyway i was insulted by many people the only time i go there not by Amir but by his disciples.... i was naive thinking people look for truth and improvement.... They look for confirmation biases yes.... But that include Amir’s disciples especially... My self i was looking about improving acoustic experience by correlating some minerals addition on some part of the gear.... Easy experiments to do....And easy to verify, by their impact on the timbre perception, less so easy to measure, i dont know...

Human hearing is able to detect very subtle change from the resonant body source of the sound, it is the way man create music and create his meaning... Some ignorant claim they could reduce this phenomena to decibel level measures for example to determine what is audible or not... Simplistic claim that say all about scientific complete ignorance of the neurophysiology of acoustic which is non linear to begin with... What is audible for human ears is qualitative features essential to our survival, not simple linearly measured numbers by simplistic tool but non linear interactive complex qualities resulting from the interaction between the sound source and the environment...

«Silence is a bias and a sound, especially when i speak with my wife»-Groucho Marx 🤓

I also suspect that our initial exposure to reproduced music informs our future choices. Unless one is Mahgister who has obviously figured everything out. Amir's measurements are a resource and he does provide data with a methodology. Flawed, maybe, but better than subjective hyperbole. 

@pabs85 

Well, if the choice were binary, then yes, I'd agree that listening would trump measuring. This can be confirmed by the fact that not all components which measure very well necessarily sound good to all ears (e.g. a dry, analytical amp), and that some well-established, highly regarded designers (e.g. Nelson Pass) intentionally add distortion to their products, as their customers prefer the resulting sound signature(s).

Of course referring to both is arguably preferable, as measurements can, at a minimum, help consumers to avoid obviously flawed products.

If you read my posts here in audiogon i NEVER rejected measures...

On the contrary i rejected objectivist and subjectivist opposition to be meaningless in psycho-acoustic where measures of different kind are CORRELATED always to subjective impressions...

Second: i promoted acoustic and psycho-acoustic EXPERIMENTS in each of my post against "subjective hyperbole" of reviewers when they spoke about their "taste" in costly gear changes.....I promoted embeddings electrical,mechanical and acoustical controls devices and experiments BEFORE any upgrade...Most upgrade are not so useful... Acoustic is...

I also suspect that our initial exposure to reproduced music informs our future choices.

Here you are right and Timbre recognition is the subjective METER by which we create our small room acoustic...

Unless one is Mahgister who has obviously figured everything out. Amir’s measurements are a resource and he does provide data with a methodology. Flawed, maybe, but better than subjective hyperbole.

Sorry but i dont think a bunch of measures so useful they can be for an ENGINEER would be useful for most people... But acoustic and psycho-acoustic knowledge will be in all case...

Measures are like food we eat them without always knowing what we eat and what for and MOST food content is transformed in waste at the end anyway...Acoustic experience is like air respiration , no waste........But we need to eat food anyway, you catch it ?

And keep your sarcasm about me for you....Thanks...

I figure out, yes, the acoustic of my OWN ROOM... This fact disturb you?

Try many hundred of listening experiments non stop on a 2 years period ( i am retired) and you will figure out yourself the basic and you will never need to give me your sarcasm anymore.....

I don’t understand Amir’s argument. I have huge experience listening, and I have a good idea about the perceptive ability to hear things, as I was an audio salesman for awhile.

 I hear differences in my system immediately after putting a new piece of equipment in. More or less details, differing tonal balance or emphasis in certain frequencies. Where the differences are small and thus difficult to ascertain (as when I auditioned the original Audience AU24 interconnect against the Audioquest King Cobra, each providing similar slightly warm tonal balance with similar detail), I don’t fret about it.

 I thought Amir went off the rails when he reviewed Schiit equipment, claiming that their products were dangerous. I don’t read him.