Master Thread: Are measurements Everything or Nothing?

[Galliardist]

So I wanted to look into the matter... I blindfolded my wife and had her do the double-blind test by asking her if she preferred to rest her face on the marble cladding of the bathroom or on the velvet sofa. 10 times out of 10 she preferred to put his face on the marble cladding in the bathroom and not on the sofa. It is useless to repeat that the temperature of the sofa and the wall were exactly the same at 26.1°C... other face of psychoacoustics

There’s a perfectly valid explanation for that. Both surfaces may be the same temperature, lower than the skin: but the tiles absorb heat faster from the skin, making them feel colder.

Physics

 

[antcollinet]

So I wanted to look into the matter... I blindfolded my wife and had her do the double-blind test by asking her if she preferred to rest her face on the marble cladding of the bathroom or on the velvet sofa. 10 times out of 10 she preferred to put his face on the marble cladding in the bathroom and not on the sofa. It is useless to repeat that the temperature of the sofa and the wall were exactly the same at 26.1°C... other face of psychoacoustics

Except it isn't. There are valid measurable reasons why marble cools the skin more than velvet at the same temperature, and why moving air cools the skin more than stationary air at the same temperature.


EDIT : Errr.. plus what @Galliardist said.

 

[widemediaphotography]

Thanks guys for the theoretical physics lesson, but the meaning of my intervention is aimed at underlining that a measurement or comparison of 2 numbers cannot always explain situations that are perceived in a completely different way, especially when they concern our sensory apparatus. If I stopped to measure the first order frequency of the same note of a saxophone or a trumpet, in the same octave, measuring the same frequency even though the two musical instruments play very differently without the need for any double-blind testing. What is the measurement that you would be able to put in place to evaluate, for example, the level of dizziness of 2 patients, hunger or tiredness?

 

[Axo1989]

So I wanted to look into the matter... I blindfolded my wife and had her do the double-blind test by asking her if she preferred to rest her face on the marble cladding of the bathroom or on the velvet sofa. 10 times out of 10 she preferred to put his face on the marble cladding in the bathroom and not on the sofa. It is useless to repeat that the temperature of the sofa and the wall were exactly the same at 26.1°C... other face of psychoacoustics

I want to hear more about the bold part. Or do I?

 

[Killingbeans]

So I wanted to look into the matter... I blindfolded my wife and had her do the double-blind test by asking her if she preferred to rest her face on the marble cladding of the bathroom or on the velvet sofa. 10 times out of 10 she preferred to put his face on the marble cladding in the bathroom and not on the sofa. It is useless to repeat that the temperature of the sofa and the wall were exactly the same at 26.1°C... other face of psychoacoustics

 

[Killingbeans]

If I stopped to measure the first order frequency of the same note of a saxophone or a trumpet, in the same octave, measuring the same frequency even though the two musical instruments play very differently without the need for any double-blind testing.

But if you measure them in the entire audible bandwidth, you'll see both the fundamental frequency and all of the harmonics. The difference becomes equally obvious in measurements. So what's the point? That you need to measure the correct things to draw certain conclusions? We already know that.

What is the measurement that you would be able to put in place to evaluate, for example, the level of dizziness of 2 patients, hunger or tiredness?

I'm not a biologist, but I'm pretty sure you can see all of those things in brain scans and/or blood work, if you know what to look for.

Just because measuments aren't always a practical practical approach, doesn't mean they are useless.

 

[antcollinet]

Thanks guys for the theoretical physics lesson, but the meaning of my intervention is aimed at underlining that a measurement or comparison of 2 numbers cannot always explain situations that are perceived in a completely different way, especially when they concern our sensory apparatus. If I stopped to measure the first order frequency of the same note of a saxophone or a trumpet, in the same octave, measuring the same frequency even though the two musical instruments play very differently without the need for any double-blind testing. What is the measurement that you would be able to put in place to evaluate, for example, the level of dizziness of 2 patients, hunger or tiredness?

Of course not - you have to compare the correct numbers. In the case of your example, the numbers that measure conductivity of marble or sweat drying on your skin. Your example doesn't need a subjective interpretation, you can even measure the effect on skin temperature for both those cases. This all comes from an understanding at a technical level of what you are measuring.

If your point is about how your perception of music is altered by things that are not in the musical signal (ie, not from the gear) then you are correct. Your mood, substance consumption and yes, feeling well or hungry or tired can all impact how the music sounds to you. Not to mention - what you see and know about the gear you are listening to. It is why blind testing is necessary when you want to compare how different gear sounds using ears/brain.

 

[widemediaphotography]

In fact, we're starting to agree that there are many ways to take a measurement and draw conclusions from it. When we say, for example, that all PCs resolve the same high resolution file equally, when run from a "bit perfect etc" player, we should somehow be able to measure and demonstrate that this is always true, regardless of EMI exposure level or power quality. In my field we carry out electromagnetic compatibility tests on cars and vehicles, as required by the standards. The tests can last up to 20-30 days, and what seemed regular in our workshops, the tests show instead that things change considerably under stress. The tests also show that the single device behaves in one way, while in the chain things change profoundly. Today vehicles, especially electric ones, have dozens of ECUs, 15 years ago 4-5!

 

[antcollinet]

In fact, we're starting to agree that there are many ways to take a measurement and draw conclusions from it. When we say, for example, that all PCs resolve the same high resolution file equally, when run from a "bit perfect etc" player, we should somehow be able to measure and demonstrate that this is always true, regardless of EMI exposure level or power quality. In my field we carry out electromagnetic compatibility tests on cars and vehicles, as required by the standards. The tests can last up to 20-30 days, and what seemed regular in our workshops, the tests show instead that things change considerably under stress. The tests also show that the single device behaves in one way, while in the chain things change profoundly. Today vehicles, especially electric ones, have dozens of ECUs, 15 years ago 4-5!

First the statement that bit perfect players resolve equally that is correct. The music signal will be identical.

When you start talking about "power quality" or EMI - this becomes an issue of noise. You can measure this also on the output of whatever is creating the analogue signal, eg the DAC on the input of whatever device is receiving the analogue signal (EG amp) **as SNR (Signal to noise ratio) IE the level of the (equally resolved) signal compared with the noise added by the system.

And here is the thing - noise is a system issue. Take the most common audible noise: ground noise. You can have two systems with equal amounts of ground noise which are either susceptible to that noise, or are able to reject it. In particular how the components of the system are connected to mains and to each other will have a significant impact on whether that noise finds its way into the speakers.

Also important to understand - ground noise will not have only one source (eg the streamer or PC). Every component connected to the loop can contribute to ground currents - as can magnetic coupling to nearby equipment - or just to the mains wiring.

Using optical interconnect for example will usually effectively reject it. So if you have a noisy PC whose only connection to DAC/AMP system is an optical tos link cable then the noise will not get onto the output. It will sound identical to any completely noiseless system.

Similarly if you use balanced interconnect in your analogue signals (eg between DAC and AMP). That will reject ground noise sufficiently to make it inaudible.

Or if you are connecting from the PC via USB you could use an isolation device - again, ground noise eliminated.

So yes - bit pefect players of whatever type will generate identical music signals if sent to the same DAC - and this can be measured. Noise is a separate topic, is system related, and is also measurable.



**Correction added - you are less likely to measure the most common form of audible noise (ground noise) on the DAC output at audible levels - unless the DAC internal grounding is poor.

 

[bodhi]

In fact, we're starting to agree that there are many ways to take a measurement and draw conclusions from it.

I'm sure the agreement was there from the start.

What I'm not sure about is that do you have some kind of claim about validity of the measurements that are used in context of ASR?

It's just that there have been quite many people in this thread who are involved in so called "muddying the waters" and avoid presenting any clear claims that could then be evaluated.

 

[widemediaphotography]

When we state that an audio quality low noise linear power supply is useless in a pc playing a file with a somewhat perfect player, or we point out the uselessness of a reclocker or a USB port filter, because DAcs are already equipped with filters, we should specify and measure:

1) Which DAC
2) What is the percentage effectiveness of the filters and up to what EMI level, and if all the filters are all the same
3) Up to what EMI level there are no differences


When the scientists here present declare that it is useless to distinguish an audio pc from a common notebook, equipped with a lot of turbo fans, we should ask ourselves if in their measurements, the microphone and the equipment are able to detect the decibels emitted by the fans or the electric hum of the HD, mouse or display and how we can swear and certify that there are no differences!

This is real science!

 

[Galliardist]

When we state that an audio quality low noise linear power supply is useless in a pc playing a file with a somewhat perfect player, or we point out the uselessness of a reclocker or a USB port filter, because DAcs are already equipped with filters, we should specify and measure:

1) Which DAC
2) What is the percentage effectiveness of the filters and up to what EMI level, and if all the filters are all the same
3) Up to what EMI level there are no differences


When the scientists here present declare that it is useless to distinguish an audio pc from a common notebook, equipped with a lot of turbo fans, we should ask ourselves if in their measurements, the microphone and the equipment are able to detect the decibels emitted by the fans or the electric hum of the HD, mouse or display and how we can swear and certify that there are no differences!

This is real science!

Hang on a minute. Why do WE have to specify and measure everything about every product of a certain type, before we can claim that the class of devices is largely useless? Every time these things ARE actually measured, through measuring the electrical output of a known good DAC with and without the product in the chain, there is no audible difference, and usually no difference at all, to be found. The same can be done at the output of the amplifier, and there is still no audible change.

Got that? Do you understand the implications of the output not being different?

So, it is not up to US to prove the claims, which often go way beyond EMI rejection, made for any of the products you list. It is up to those making the claims. But, once again, we have a "scientist" riding into the WIld West of audio, coming into town and shooting the concerned citizens and leaving the bad guys alone.

If you want proof that these products work, try taking it up with the manufacturers, get them to prove that their products work, directly, in the public arena via a clear measurement that can be repeated by somebody independent and via a proper double blind test. It is not Amir's job or anybody else's here to do that. In the spirit of investigation, every so often one of these devices gets tested, and the output doesn't change. There comes a point when our experts should be left to deal with products and techniques that do make a difference to the sound, surely?

Of course, if you have the capacity to do all those things you say, and access to the equipment to do it, you're welcome to try and prove that one of these products really is of value in an audio system at a given level of EMI (also proving that the practical working conditions in a home audio setup will ever reach that level of EMI pollution), and publish the test protocols and results here when you have that proof, so that anybody else can replicate the experiment and get the same result.

My guess is that we'll be waiting a long time for you to do that, though.

 

[JustJones]

I kind of like this thread, it gives me a feeling of deja vu.

 

[bodhi]

I kind of like this thread, it gives me a feeling of deja vu.

What amazes me is that people start going at it in high spirits with dirty debate tactics from the stone age when the thread has 8000 messages already. What do they think will happen?

 

[TankTop]

Just skipped 364 pages to post a rant…

Chatting (chatting is a very liberal term here) with someone on another forum, almost every time I commented on a speaker they responded with something about how the speaker didn’t measure well on ASR and that they’re a speaker designer. Finally had to block them.

Yes measurements matter! At the same time there are lots of speakers that don’t measure great in every category that are still regarded as excellent speakers and very enjoyable to listen to. No need to be a measurement nazi if someone says XYZ speaker is great and they enjoy listening to it even if it doesn’t measure well.

A Mazda Miata handles better than most uber expensive super cars and if given the choice I’m taking a 911 over a Miata every time. A JBL Stage A120 measures better than a Focal Sopra but I’m guessing if it was an A/B choice most here are taking the Sopra.

Some of the best music and memories were with a factory soundbar in my Wrangler with the top off and two girls the same. There is something to music that touches the soul and brings back memories that you can’t measure with even the meat equipment.

Let me add: the purpose of ASR is to test audio equipment and educate. Once educated let people make their own decisions based on personal preference and for the love of god don’t stalk them around the internet spouting off about measurements… if you read this and you’re effended ease get a life

 

[Galliardist]

What amazes me is that people start going at it in high spirits with dirty debate tactics from the stone age when the thread has 8000 messages already. What do they think will happen?

The thread's a dumping ground, primarily for off topic posts in review threads that are general challenges to the value of measurements - they get moved into this thread.

What amazes me is that so many of the people who turn up are apparently high level engineers and scientists, yet it all goes completely out of the window when it's time to defend their favourite magical thinking in the audio field.

 

[antcollinet]

When we state that an audio quality low noise linear power supply is useless in a pc playing a file with a somewhat perfect player, or we point out the uselessness of a reclocker or a USB port filter, because DAcs are already equipped with filters, we should specify and measure:

1) Which DAC
2) What is the percentage effectiveness of the filters and up to what EMI level, and if all the filters are all the same
3) Up to what EMI level there are no differences


When the scientists here present declare that it is useless to distinguish an audio pc from a common notebook, equipped with a lot of turbo fans, we should ask ourselves if in their measurements, the microphone and the equipment are able to detect the decibels emitted by the fans or the electric hum of the HD, mouse or display and how we can swear and certify that there are no differences!

This is real science!

When did anyone mention "equipped with a lot of turbo fans"

Most laptotops are not. I'm using a macbook - and the fan never comes on unless I'm doing something that maxes out all the processors. A pretty rare event. And if it happens when I'm listening to music, then I'd be having that problem even if I was playing the music with a separate streamer.

And USB filters. They are incredibly useful for eliminating ground noise if your system suffers from that - though in that case better to switch to optical toslink instead. They are utterly pointless for re-clocking/jitter elimination - which is simply not a thing in modern USB audio.

You need to stop throwing straw men around willy nilly - else we'll run out of things to scare the crows. Or at least try to understand the arguments that are actually being made, and how the technology actually works, and how it can be used to eliminate the whataboutism problems you seem to struggle with.

 

[Deleted member 21219]

What amazes me is that so many of the people who turn up are apparently high level engineers and scientists, yet it all goes completely out of the window when it's time to defend their favourite magical thinking in the audio field.

I agree, yet I'm always aware that people may not be what they appear to be.

Jim

 

[widemediaphotography]

Unfortunately we are generalizing a lot even for things that should be treated differently.

I ask a very simple question, which still finds uncertain answers.

In the same audio chain,
Anyone who is able to establish that an ordinary notebook and a PC, built following audio criteria, in all operating conditions and in all parts of the world, running the same flac file with a somewhat perfect player, always acquires the same audio stream from the speakers and is always perfectly superimposable.

I say to demonstrate, to those who are able to do it, that an audio pc (low noise audio grade linear power supply, fanless, USB reclocker and USB filters) is perfectly useless compared to any other PC when playing a file with a somewhat perfect player of any nature, and regardless of the audio chain!

To answer someone... I've already asked manufacturers of filters, reclockers and audio power supplies (they're not all the same)...
For example, from my tests an Amazon USB printer cable sounds exactly like a $500 DAC cable (double-blind test done 20 times on different days and not even adding ferrites)! But interconnect cables are one HW devices thing another.

Going back to the discussion that is immediately clear if you are dealing with engineers or other, you understand it when they say that in an audio cetana for the transport of a digital signal (max 2 meters) it is preferable to use a Toslink optical connection which instead implies a double conversion, which in the best case scenario does not introduce further jitter.

 

[antcollinet]

If you take one single super high end streamer device - it won't output "superimposable" audio streams in all operating conditions in all areas of the world.

You are not even trying to argue in good faith now.

Blocked.