Sound Quality Vs. Measurements

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No, I don't believe that.
If one of the amps is misbehaving then it will show in the measurements.
If both amps are behaving equally well and both are not clipping, then they will sound (substantially) the same.
Why? Because the measurements show that they amplify all the audio content exactly equally, particularly the transient content. Continuous and constant sinewaves do not reveal much about the amplification behaviour of amplifiers. Well 19k+20k imd is an exception.

Andrew, with all due respect to you, but I find your argument that if the measurements are the same then the sound will be the same to be ridiculous.

A pity we don't leave reasonably near each other - I would love to give you an amp which measures very well indeed but manages to sound dry and disinterested, and another which doesn't measure half as well, but will make you tap your foot to the rythm inside of 5 minutes.

I would just LOVE to hear your comments afterwards.

I would like to remind you that way back in the 70ies, one Julian Hirsch, co-owner of Hirsch-Hook Labs, which did measurements for various US magazines (including AUDIO to which I was subscribed), claimed exactly the same thing - if they measure the same, then they sound the same. Within two months, he was fired from each and every magazine he worked for, and as far as I know, simply sank into oblivion after that (people from the US, please correct me if I'm wrong about his demise).

Andrew, if what you claim was true, there would be no poor amps anywhere to be found, all would be very good. Yet, it is not so, is it?
 
Measurement of seemingly benign input coupling capacitors reveals mangling of phase to >100Hz, although frequency response appears flat in same region.
a-ha!
dvv said a few pages back that that can be avoided by a good choice of cap value. obviously but what do we do about the ones (hundreds, likely) that were there in the studio gear? :)
I remember reading on Siegfried Linkwitz's webpage that he suspects phase to be an issue even in the sub 100 Hz region. which makes a lot of sense, because it's not a region where 1 deg of shift equates a head movement 0.1 millimeters. but it looks to me that random speculation is preferred instead of actually testing that.

Andrew, with all due respect to you, but I find your argument that if the measurements are the same then the sound will be the same to be ridiculous.
no-one denies you that opinion :) but it should be settled: is this forum a place where opinions are allowed to be made facts? oh, sorry, I forget: it is :D

A pity we don't leave reasonably near each other - I would love to give you an amp which measures very well indeed but manages to sound dry and disinterested, and another which doesn't measure half as well, but will make you tap your foot to the rythm inside of 5 minutes.
Andrew replied to a post of yours that said amps measuring the same sound different. here you're talking about amps that measure differently.

I would just LOVE to hear your comments afterwards.
huge mistake here.
you are making assumptions about the "opposing" (note the quotes which mean that I don't view this as some kind of war) camp's POV. the "opposing" camp is not proclaiming what you think it is proclaiming.
 
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Whatever a person's background, it doesn't make them immune to expectation bias. The very act of chopping out the old capacitors covered in dust and grime, symbolically dumping them in the bin, getting out shiny new caps and soldering them in with care and attention, smartening up the wiring better than before, vacuuming the dust out. Then the anticipation of powering up, selecting a test track. How could it not sound better!?

While in reality, of course, it sounds exactly the same as before, when it was using caps 35+ years old, which when measured for the most basic aspect of all, capacitance, now have less than 7,000 uF from nominally 15,000 uF caps?

But there is some truth in what you say, I've witnessed it myself a number of times. People think one small move will get them the world, and when instead of getting it they get a modest improvement, they feel sort of cheated.

In my experience, the improvement will ALWAYS be there where a number of 35+ years old components are exchanged for new ones, and even more so when the new ones happen to be high quality components, and possibly even more so if they upgraded the components. Say, took out those rated at 6,800 uF 35 years ago and installing quality new ones rated at 10,000 uF.

And while an improvement will heard rather easily, it is not likely to be a revelation, no sudden light from the sky, no epiphany, no heavenly choire of angels. Quite simply, the amp is allowed to do the best it can, but in the end, it will alway be its design which will impose the final frontier.

But, there's no doubt some placebo effect will be in play. The more reasonable will have it in much smaller doses than the less technically inclined.
 
Measurement of compression with DEQ2496 shows addition of harmonic distortion. Distortion increases with shorter release times.

That's what I would expect, I suppose, but very interesting. So the extra THD, you're saying, comes from 'feed-through' of the signal to the gain adjustment i.e. a small amount of the un-low pass filtered signal makes its way to the gain adjuster..? In your test, what sort of increase in distortion are you seeing?

If so, presumably such an effect was always present with DBX-type noise reduction? And also with any compressor used when mastering a recording. I could conceive of DSP-based compression that can look ahead and intelligently apply compression to a recording with the bare minimum of added distortion.
 
a-ha!
dvv said a few pages back that that can be avoided by a good choice of cap value. obviously but what do we do about the ones (hundreds, likely) that were there in the studio gear? :)


no-one denies you that opinion :) but it should be settled: is this forum a place where opinions are allowed to be made facts? oh, sorry, I forget: it is :D


Andrew replied to a post of yours that said amps measuring the same sound different. here you're talking about amps that measure differently.


huge mistake here.
you are making assumptions about the "opposing" (note the quotes which mean that I don't view this as some kind of war) camp's POV. the "opposing" camp is not proclaiming what you think it is proclaiming.

In which case, I do apologize for my mistake, I misunderstood.
 
While in reality, of course, it sounds exactly the same as before, when it was using caps 35+ years old, which when measured for the most basic aspect of all, capacitance, now have less than 7,000 uF from nominally 15,000 uF caps?

The story was that a veteran audio designer's training told him it should sound no different, so I don't think the caps were 35 years old and measuring down significantly.

As it happens I recently measured some 1978 electrolytics (35 years old!) in a Kef speaker and they were almost spot on, as indicated by a multimeter (not a definitive assessment I realise). I'm still going to replace them, but I'm not kidding myself they'll sound much different.
 
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On occasion I have definitely heard strong differences that later were shown to be non-existent.

You reckon you're immune to all of this, do you?
https://en.wikipedia.org/wiki/Experimenter's_bias

The irony is that if a person is unaware of their own biases they begin to feel like some sort of ultra-receptive 'seer' who can perceive differences that lesser mortals can't; differences that don't even show up in any of the puny measurements that mere meter-readers dream up. Their ignorance and weakness actually bolsters their feeling of superiority and omnipotence.
No need to rev up about it ... it's just that this 'bias' thing seems to be dragged out like an convenient salve every time experiences or anomolies don't nicely fit into well known, easily measured scenarios. We are dealing with human hearing here, which can be remarkably acute, or stupidly insensitive, depending upon an enormous number of variables.

Personally, I would like everything I try fiddling with to improve the sound, but that 'bias' hasn't worked for me: I have 'kicked the cat' on many occasions in frustration because I kept going backwards, or nowhere. Only by taking long breathers, for days, weeks -- and many years once -- have I slowly moved forward. I'm my own severest critic, I'll be the first to switch off in disgust, because a 'good idea' ain't ...
 
In which case, I do apologize for my mistake, I misunderstood.
maybe it doesn't stand for others. but I for one am trying to see a correlation based on actual tests made in statistically-significant numbers and in the correct context (e.g. all factors unchanged etc). I'm not naive, I do understand that such tests are tedious, time-consuming and costly. in a word, unlikely to be done by DIY-ers. I would bet that many makers have a pretty good idea about why stuff sounds like it does. but, being such a playground where stuff is sold by the hundreds or less to a niche (actually sometimes it's a niche of a niche of a niche) of the market, it's unlikely that they often go public :D

regarding biases of all sorts. as simple as this is, don't expect many people to agree. fact is that it does happen. not always, but it does happen. it should be excluded as an explanation for different sound on a case-by-case basis, not always.
the same goes for the never ending story of ABX (or any sort of DBT) testing. yes, it has its problems, obviously. and they should be acknowledged. but acknowledging some problematic portion of the issue doesn't make the whole thing wrong. but, again, this generalization game goes with the trade, I don't expect that we free ourselves from the problem any time soon :)

thing is I'm not all against empiricism and subjectivism. but I started being a skeptic the moment I realized that many of the explanations of perceived differences are plain-out wrong and deny the most basic established facts and even logic. you hear a difference? fine, no problem, I even take you for granted. you provide an explanation that doesn't hold water? I have a problem with that.
 
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The story was that a veteran audio designer's training told him it should sound no different, so I don't think the caps were 35 years old and measuring down significantly.

As it happens I recently measured some 1978 electrolytics (35 years old!) in a Kef speaker and they were almost spot on, as indicated by a multimeter (not a definitive assessment I realise). I'm still going to replace them, but I'm not kidding myself they'll sound much different.

Yes they did, and I should know, I took them out of my Marantz 170DC power amp myself. Nominally 12,000 uF, it measured at just under 7,000 uF, as did my Marantz integrated 1152DC. In both cases, the caps were by Elna. In both cases, they were replaced by BC Components 22,000 uF caps. Then all of the other caps were replaced.

And they sounded a hell of lot clearer and composed than with the old caps, make no mistake.

Both were manufactured in March 1978, as per the factory stamp inside.

As for sounding "much" different, well, that also depends on what you consider as significant enough to be called "much". In my book, anything I can hear straight away is much, what I have to listen for two hours to catch a bit better here and there I would not call much.

However, what you choose to believe is your business. You clearly stated that you don't believe in the truth as told by the man who did it, so after that, it makes no difference what you think, I'm afraid, because you were not there, you did not measure them, and so forth. Therefore, you believe in your make believe truth, right?
 
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thing is I'm not all against empiricism and subjectivism. but I started being a skeptic the moment I realized that many of the explanations of perceived differences are plain-out wrong and deny the most basic established facts and even logic. you hear a difference? fine, no problem, I even take you for granted. you provide an explanation that doesn't hold water? I have a problem with that.

However, not knowing what makes the difference does not mean that the said difference is not there.

So far, nobody has created a test, or a series of tests, which can reliably quantify musical sastifactiion, real quality, etc. Audio does not cater to measurements and oscilloscopes and microphones, it caters for people, who are all, by definition, different one from another on the metal level.

To take an extreme case, it's one thing how a steel mill worker will hear the same music as a trained musician. For any number of reasons. The steel mill worker is exposed to mammoth machinery which is very loud, and drones in his head 9 hours every day - that alone is a grand difference.

When I hear a difference between two amps, at the time I am hearing it I have no idea what causes it, discounting the most obvious failings of any comparison which I would not make, like comparing one 30WPC and with a 150WPC amp, using program material in a setting which requires peaks of say 100 WRMS. Aside from such obvious mistakes, no idea why. Nor do I, as a user, really care.

If, for example, Frank can stun me with his chip amp to the point where I think that what I am hearing is better, I'll dump my Karan and never look back and buy Frank's. It's that simple, I don't give a damn about the manufacturer, price tag, built-in bling, etc, I just want the kind of sound I like, period.
 
Yes they did, and I should know, I took them out of my Marantz 170DC power amp myself. Nominally 12,000 uF, it measured at just under 7,000 uF, as did my Marantz integrated 1152DC.
...
However, what you choose to believe is your business. You clearly stated that you don't believe in the truth as told by the man who did it, so after that, it makes no difference what you think, I'm afraid, because you were not there, you did not measure them, and so forth. Therefore, you believe in your make believe truth, right?

You never mentioned the measurements in your original anecdote, and why did you say that this man's training told him there should be no difference..? I was just going on what you told me. If you had originally stated that the caps were measuring half their value I would not have questioned that they should sound different when changed. So in reality the story boils down to "I changed some *35 year old* caps that were *measuring at half their original value* and the new ones sounded better. I don't think you'll be dining out on that story for many years to come.
 
However, not knowing what makes the difference does not mean that the said difference is not there.
who pretended otherwise?
actually, it's the subjective camp which asserts that those differences are unexplainable by any measurement. which makes a lot less sense.


So far, nobody has created a test, or a series of tests, which can reliably quantify musical satisfaction, real quality, etc.
I think that somewhere in the 70s they had predicted that by 2000 all physical work will be done by robots. I guess we all agree it didn't happen. but that doesn't mean it will never happen :)
and, actually I remember reading a post by ThorstenL (can't remember where) where he wrote that some guy from Germany requested test subjects to evaluate the sound they heard on a scale based on enjoyment.
othe other factor (which you mentioned below) is that as long as there aren't any gross aberrations like a tonal balance that went to lunch, preferences start to matter. but the subtext implies that certain preferences are better than others :)


Audio does not cater to measurements and oscilloscopes and microphones, it caters for people, who are all, by definition, different one from another on the metal level.
first, you are misrepresenting a POV. no one said that audio is about oscilloscopes.
second, the fact that there are different preferences is not exactly related to the ongoing discussion. if you prefer high slew rate amps it says nothing, because what you're actually preferring may be caused by other factors that are coincidentally related to SR. and if you prefer a certain sound and you achieve that by cap swapping, does it mean that the only way a certain type of sound can be achieved is by cap swapping?


To take an extreme case, it's one thing how a steel mill worker will hear the same music as a trained musician. For any number of reasons. The steel mill worker is exposed

to mammoth machinery which is very loud, and drones in his head 9 hours every day - that alone is a grand difference.
IME, there is absolutely no correlation between being an audiophile, musical training, musical tastes, education etc. I've met people with huge music collections and very eclectic tastes that enjoy music listened to on boomboxes. some other people are audiophiles but play the same "Best Audiophile Voices" as infinitum. I quoted Eberhard Weber in another thread. he said that it upsets him when people ask him what strings he uses, he simply doesn't care. I think (maybe I'm wrong) that you're trying to make certain people look bad.


Nor do I, as a user, really care.
just as you find pleasure in cap swapping and you pitty us (I fit into that category, thanks a lot btw) types who don't do it, maybe, just maybe, there are people who find enjoyment in music listening and at the same time find some "weird" intellectual or academic enjoyment in correlating some objective parameter with sound. Nigel suggested the suffer from OCD behavior :) no self-appointed superiority there, not the slightest trace of it, I'm sure.
after reading the quoted phrase I can speculate on why there's not any actual scientific attempt to correlate sound with measurements in high-end: not trying at all certainly goes a long way when it comes to not achieving it :)


If, for example, Frank can stun me with his chip amp to the point where I think that what I am hearing is better, I'll dump my Karan and never look back and buy Frank's. It's that simple, I don't give a damn about the manufacturer, price tag, built-in bling, etc, I just want the kind of sound I like, period.
it's not about Frank. I would guess that some of the people writing here have superior sounding system ad yet they don't adhere to the "empirical" camp.
 
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dvv said:
I would love to give you an amp which measures very well indeed but manages to sound dry and disinterested, and another which doesn't measure half as well, but will make you tap your foot to the rythm inside of 5 minutes.
You will be aware, of course, that this is anecdotal evidence for euphonic distortion which Occam suggests we should adopt as the simplest explanation for preference for poorer measurements.

Someone needs to do a DBT using Wavebourn's 'niceness' control. The listener is free to adjust the knob to get the 'best' sound, but he won't know (and the experimenter won't know) which knob position gives undistorted sound. After the test we can see. Something like this was done in the 1950s (probably only single-blind, but I can't find the reference) and it showed a preference in most people for a little 2nd-order.
 
We are dealing with human hearing here, which can be remarkably acute, or stupidly insensitive, depending upon an enormous number of variables.

Just words. Who says that our hearing is remarkably acute or stupidly insensitive, in any sense that matters to the question in hand i.e. can sound quality be measured? For all we know, our ears can really only discern gross errors; maybe none of us can discern the difference between amps or DACs, but almost none of us has ever taken the time to prove it, nor would most people want to prove it. I genuinely don't know whether I could tell the difference between a LM3886 and a Krell because I've never done a proper unsighted test. If I had to bet, it would be that I couldn't, until they were very loud indeed. However, taking that test would immediately destroy what few credentials I might have in the audio world.

Personally, I would like everything I try fiddling with to improve the sound, but that 'bias' hasn't worked for me: I have 'kicked the cat' on many occasions in frustration because I kept going backwards, or nowhere. Only by taking long breathers, for days, weeks -- and many years once -- have I slowly moved forward. I'm my own severest critic, I'll be the first to switch off in disgust, because a 'good idea' ain't ...

Again, just words. Expectation bias or confirmation bias, or any of the other biases we are all influenced by, can take the form of imagining the best, or the worst. If a brain worm takes hold that tells you RF can rob music of its sparkle and vitality (without showing up on measurements of course) you may be pleasantly surprised what comes from an Aldi TV when you turn your mobile phone off. Or alternatively you may never hear good music again until you've turned your room into a complete Faraday cage. (I've gone through similar phases myself).
 
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