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Has anyone bought a product because of a recommendation on ASR?

What are the tolerances though. Heightened measurements don’t suggest something is broken or not well engineered. There is a nerdish anal element to all of this. If they’re way out that’s likely a problem but I suggest many aren’t way out therefore ranking them is just a numbers game.There may be minor variations which have little or any impact on quality of engineering or output.
 
b) arguably to test whether products are well engineered on an assumption that this matters either "just because" or because it inclines one to suspect that if well engineered in this respect it is, all-else being equal, more likely to be well engineered in other respects.*
This assumption sounds reasonable but often doesn't hold.

We tend to get what we measure. Musical Fidelity, Chord, dCS, Violetric all manage to make DACs with an output impedance around 1 ohm via XLR. Chinese DACs all 100 ohms (one exception at 50 ohms) - this wouldn't be the case if ASR measured that as standard (as SoundStage and Stereophile do).

Is 1 ohm output impedance audible? My question: is -130dB distortion audible?

Those who create a culture of measurements-are-everything, create a glass house for themselves to sit in. And if they preach from that glass house, stones will be sent.
 
Indeed. The purpose of measurements is not to describe what things sound like, it is to assess the proper functioning of the device. Yet so many people subvert measurements into a value judgement about audibility, sound quality and all the other things. It comes from both sides of the argument, IME.

I find it even more bizarre with DACs as theoretically all of them measure pretty much perfectly and have done for decades. The frequency response is always less than 0.5db right across the audio band, distortion is down at the 0.0x% or better, and signal to noise >100db (for context the background noise in a very quiet room is around 40db). They should all sound the same. Yet they don’t.

My disappointment with the current obsessive measurements thing is the lack of useful correlation between measured evidence and user-perception. If one takes a look at post #144 upthread, a subjective end-user appraisal of some very well reviewed and well measuring DACs, until we get to the point where the raw data can be interpreted to predict such subjective findings it is IMHO next to useless.
 
, until we get to the point where the raw data can be interpreted to predict such subjective findings it is IMHO next to useless.
Why assume that the subjective finding are purely the result of an input via the Vestibulocochlear nerve? If not then maybe you are looking at the wrong data.
 
Audibility and sound quality are two completely different things.
Well yes quite. It was a list.
One which joined items in a way which suggested that the compiler was simply muddled. There is no reason why (given empirically established models) a measurement cannot in some cases predict (actual) audibility. Mind you a "value judgment" about audibility seems a bit confusing too. Of course if your point is that the measurement cannot predict whether someone will think that two audibly indistinguishable things "sound different", then fine.
I'm sorry you got the impression I was muddled. I'm not sure how a list of: 'audibility, sound quality and all the other things' suggested the first two were joined, but if you did, then perhaps I could have worded it more clearly. Open to suggestions; perhaps the use of an Oxford comma might have made it clearer that it was a list, but then again, the two items you conjoined were indeed separated by a comma so I'm out of ideas.

For clarity, measurement afficonados often use the fact that an artefact is at, say -130dB, to argue that the artefact is inaudible, because noise floor, etc.etc. This is the 'value judgement - often an implied 'value judgement' on the interlocutor, but hey. The 'proper' value judgement is of course in the assertion that the measured artefact is of no consequence, because it is below the audible threshold. I had assumed this would be clear enough. Whereas other people also point to intermodulation or interaction between artefacts and other elements of the signal as creating audible effects, so the audibility point is at least debatable. I was merely pointing out that the question of 'audibility' is, like 'sound quality' and 'all the other things', one of those matters where people cite measurements in support of their stated position.
 
I was merely pointing out that the question of 'audibility' is, like 'sound quality' and 'all the other things', one of those matters where people cite measurements in support of their stated position.
I see
Indeed. The purpose of measurements is not to describe what things sound like, it is to assess the proper functioning of the device. Yet so many people subvert measurements into a value judgement about audibility, sound quality and all the other things. It comes from both sides of the argument, IME.
It seemed as though you were saying that citing measurements in support of an assessment of audibility was a misuse ("subvert"), which (if done sensibly) it is not. This is quite different from the issues surrounding the use of measurements to say what something sounds like or "sounds like".
Incidentally as we all know some designers are happy to design electronics entirely from measurements.
 
I see

It seemed as though you were saying that citing measurements in support of an assessment of audibility was a misuse ("subvert"), which (if done sensibly) it is not. This is quite different from the issues surrounding the use of measurements to say what something sounds like or "sounds like".
Incidentally as we all know some designers are happy to design electronics entirely from measurements.
I think you are overlooking my phrase 'so many people...'
 
For clarity, measurement afficonados often use the fact that an artefact is at, say -130dB, to argue that the artefact is inaudible, because noise floor, etc.etc. T
I am trying to remember who (a famous designer, I think?) said he can hear things buried in the noise. So the noise floor isn't a cut-off point. If I ever* remember I will come back to it.
* Not likely, I forget what day it is!
 
I am trying to remember who (a famous designer, I think?) said he can hear things buried in the noise. So the noise floor isn't a cut-off point. If I ever* remember I will come back to it.
* Not likely, I forget what day it is!
ISTR Rob Watts saying something very much like that.

I think his point, and one I have sympathy with, is that sometimes you don't realise something is there, until you hear an instance when it isn't there. So, it's 'inaudible' right up to the point where you hear what it's like when it genuinely isn't present. Then you can detect it, now you know how it manifests itself.
 
I am trying to remember who (a famous designer, I think?) said he can hear things buried in the noise. So the noise floor isn't a cut-off point. If I ever* remember I will come back to it.
* Not likely, I forget what day it is!

That would be rob watts of chord fgpa implementation, he has a few YouTube canjam talks on the matter of a -300db noise floor, whether or not you believe him is another matter.

I had a chord mojo 2 and poly, it was good but I sold it as my iPhone dongle sounded just as good.
 
So glad I don’t have the burden of golden ears like some of these designers. It’s going to cost me so much less in the long run.
 
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I am trying to remember who (a famous designer, I think?) said he can hear things buried in the noise. So the noise floor isn't a cut-off point.
It's true up to a point. You can hear sounds with an amplitude lower than the total noise level across the audible range. But AIUI you can't hear sounds with a amplitude lower than the noise level in the particular frequency bin (out of the bins into which your ear divides sounds) into which that sound falls. So in the case of 16 bit audio you can resolve a tone down to about -115dB below signal, unlike a measurement device which can resolve it at a much lower level because it can in effect divide the noise floor into an unlimited number of bins .

This is just one tone in the presence of noise with the sound turned up really high - if there was another tone at a much higher level your chances of resolving the -115dB tone are slim, however loud you turned up your stereo..

Alternatively if you take one phon, being the experimentally established quietest sound one can possibly hear*, then that would be 120dB below the loudest sound one could listen to, even for a very short period. Hence we can be pretty sure that something which measures at -120dB could never be heard on anyone's stereo (assuming it was not turned up to a volume which would seriously harm you) ever, even ignoring masking effect or noise floors.

* Yes such a thing exists.
 
Rob Watts came in for a lot of abuse because people thought he was saying he could hear things at, iirc, -300dB. If I've got it right he was actually claiming that he could hear, in the audible range, the effect of something at -300dB. Mind you some folk just wanted to jump on anything he said to rubbish it.
 
Rob Watts came in for a lot of abuse because people thought he was saying he could hear things at, iirc, -300dB. If I've got it right he was actually claiming that he could hear, in the audible range, the effect of something at -300dB. Mind you some folk just wanted to jump on anything he said to rubbish it.
Correct. He said that, as he was discussing the mathematical calculations that exist inside the FPGA, he could hear signal correlated noise artifacts even when those anomalies were at or near -300dB. He didn't claim he could hear those things, he claimed that that those things bore on the actual analog output at -120dB SNR, after that math was executed inside the FPGA down to a level of precision of -300dB. His next sentence, in one talk, was that obviously we cannot output beyond around 21-21.5 bits right now because the micro-voltages are so low that we physically cannot reproduce that with current manufacturing processes.

I'm not endorsing what he said. I can't even validate it.
 
I've often wondered if the ASR cognoscenti all just buy the cheapest -124 dB DAC on Amirs list, surely daft to pay more?
 
... is -130dB distortion audible?

Those who create a culture of measurements-are-everything, create a glass house for themselves to sit in. And if they preach from that glass house, stones will be sent.
I assume you mean -130 dB FS :). But maybe an alternative to "is it audible?" is "does it matter?"

I don't see any problem with people chasing "the best" as part of their hobby. For me though, by the time a DAC has a noise floor there it's in excess of my definition of "good enough". So it becomes something I can ignore. Heavens, I enjoy listening to 1950s opera; and the noise floor of the tape machines of the time is way higher than that. Indeed the noise floor of pristine vinyl of the very best quality is higher than that. Even 1990s CDs often have obviously higher noise floors than ones produced this side of 2000. This is even obvious on my 2004 CD player as well as my 2018 one. This does not impact my appreciation of the music. Others may disagree of course - it's their hobby.

And to add to your last point above, I am less than impressed by people occasionally throwing rocks at other forums for what they think is their members' ways of pursuing "the best". Is pursuing the best SNR any different in principle from pursuing DACs with 1million+ tap filters? I think not. So if someone throws stones maybe they should be aware that they may also land somewhere closer to home.
 
I assume you mean -130 dB FS :). But maybe an alternative to "is it audible?" is "does it matter?"

I don't see any problem with people chasing "the best" as part of their hobby. For me though, by the time a DAC has a noise floor there it's in excess of my definition of "good enough". So it becomes something I can ignore. Heavens, I enjoy listening to 1950s opera; and the noise floor of the tape machines of the time is way higher than that. Indeed the noise floor of pristine vinyl of the very best quality is higher than that. Even 1990s CDs often have obviously higher noise floors than ones produced this side of 2000. This is even obvious on my 2004 CD player as well as my 2018 one. This does not impact my appreciation of the music. Others may disagree of course - it's their hobby.

And to add to your last point above, I am less than impressed by people occasionally throwing rocks at other forums for what they think is their members' ways of pursuing "the best". Is pursuing the best SNR any different in principle from pursuing DACs with 1million+ tap filters? I think not. So if someone throws stones maybe they should be aware that they may also land somewhere closer to home.
There is a difference between chasing such objectives for their own sake and using equipment, whose designers have pursued such objectives, because it sounds better at recreating music in our homes. Mind you, to come to any sort of conclusion for the latter takes time and, most importantly, listening.
 


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