Did Amir Change Your Mind About Anything?

@manuelguerrahr 

I can’t believe I have not received one darn response.

...probably because you are posting on the wrong thread AND this is a discussion forum rather than a sales forum.

@kevn 

Thank you for your quick response, amir. I hope you won’t mind if I can clarify an issue (I realise how many queries you are attempting to answer at the same time, so I fully understand if you missed this) - 

My question was if you could advise if the test was a good way to gauge listening ability, but your reply involved "Methods for the subjective assessment of small impairments in audio systems", training and learning.

My question did not have anything to do with a method, or training, or audio systems, just whether the test, even if intended to have participants give a ‘no, there is no difference’ answer; only if you could advise if it was a good starting point to gauge ‘listening ability’.

You have me at a disadvantage as I thought I clearly answered your question.  Once again, no, it is not a proper test so doesn't make for a good starting point or any starting point for that matter.

It reminds me of buying a Japanese learning CDs years ago at an airport.  It claimed full immersion and quick learning.  I start the lesson and first thing it wants to teach is the words for Horse and Jockey!  I am pretty sure that should not be the starting point to learn any new language unless you are into horses.  :)

But tell me what you concluded about the results of the tests you ran.  Who had good listening ability and why?

@mahgister 

Thanks for the discussion... I learned a lot... i am not qualified in any way, i am not an engineer, but i know how to read... And Hans Van Maanen is more than qualified here... I read his very simple and very clear articles among others

My pleasure.  You make a key point here.  Just like you, other audiophiles can read too.  So audio marketing people will throw big sounding technical words that often they even don't understand to then make a technical claim they don't have to prove.  Said audiophile draws inferences from everyday life and the sale is made. 

Cable maker says said wire needs 200 hour break in.  Audiophile remembers that cars used to have such break in periods and automatically believes that wires must also need the same.  

You should be skeptical of these claims when they are provided with no proof points, either in the form of measurements or controlled listening tests.  You have post repeatedly on topic yet you have not provided anything like this.  Reading your comments, and please forgive me for being blunt, it is very clear that you are not understanding the mathematical nature of the topic being discussed or its relevance to measurements or audio equipment performance.

To wit, you keep saying there is something wrong with all the measurements we run.  Well, yesterday I reviewed the Roksan Attessa streaming amplifier. Here is our dashboard including FFT on top right:

The Fourier transform is decomposing the innocent looking time domain scope measurement on the left and warning us that the power supply is generating a ton of hum and noise.  So much so that it is higher than the distortion the amplifier is producing!  Pure, voltage (time) domain analysis of noise showed the problem again:

Notice that it can't even clear the noise floor of 16 bit music at full power let alone at my reference 5 watts.

Are you going to claim that this is a well engineered amplifier and these measurements are not probative because you read a paper on Fourier uncertainty principle?   Before you say yes, let me tell you that the owner had heard this same amplifier at a dealer and distinctly detected hum in one channel.  He wanted to find out if this was a real problem with all units produced so purchased the new unit and had it drop shipped to me.  Measurements conclusively predict and prove what he heard.  Not only that, it pointed to where the fault in design is.

This amplifier had universally raving reviews online until mine came out.  Stereophile had measured it and found SNR that was much worse than that but swept it under the rug with politically correct language.  

My, again time domain, measurements also showed very audible spike when the unit is powered on and off:

Another own this morning post that he indeed hears those pops in his amplifier.

None of this was done to verify some spec.  No performance spec is provided by the company anyway.  

You paid $3,200 for an amplifier that is not as silent and clean as a $100 amplifier I have tested recently.  

You see the power of measurements to quantify audible issues?  You see how the theory you read in that one paper does not at all related to any of this?  You see how you should challenge the one designer to produce proper measurements of his amplifier and controlled listening tests showing some benefit in his design approach?

I have read the papers you keep quoting.  I will say once again, they have no bearing whatsoever on the topic we are discussion. Go ahead and quote where Oppenheim and Magnasco say anything about audio measurements being obsoleted by that experiment.  You won't find it.

@soundfield Where are your speaker measurements? 

@amir_asr Why did you close Erin's thread?

@amir_asr Why did you close Erin's thread?

Answer was clearly given and in detail in my post when I closed the thread.  Your question has been repeatedly answered here as well. That you don't accept the answer is not my issue.  It is yours.  Disagree and move on.