vuki said:
Do you think you were objective in choosing the "cold" "soft" and "dirty" subjective adjectives?
vuki said:
I think what you call 'cold' isn't the music signal at all. The music sounds pretty undistorted, taking in account that the difference has been boosted perhaps 40dB or more. What you call 'cold' is in fact noise, hum and what sounds like power supply artifacts.
Now, in the case of the AV amp, there is clearly distortion in the sound itself (as well as that noise etc).
This is one hell of a playtool!
Jan Didden
sin08:
Of course I'm not objective, but if that is how you look on the audio, then, I think, we don't share the same hobby - your hearing apparatus should have at least some importance at judging audio devices.
I think the majority of the listeners would agree that HT amp artifacts from the sample sounded "dirty" compared to the other two. You don't need to do distortion analysis to find that out.
jan:
When listening to those artifacts I try to get the same loudness of music (purely subjective), and I think the Hafler sample has much more PS noise and hum than D-class but still sounds cleaner.
I agree this is great toy.
Of course I'm not objective, but if that is how you look on the audio, then, I think, we don't share the same hobby - your hearing apparatus should have at least some importance at judging audio devices.
I think the majority of the listeners would agree that HT amp artifacts from the sample sounded "dirty" compared to the other two. You don't need to do distortion analysis to find that out.
jan:
When listening to those artifacts I try to get the same loudness of music (purely subjective), and I think the Hafler sample has much more PS noise and hum than D-class but still sounds cleaner.
I agree this is great toy.
Jan, I can appreciate that you find this important and interesting. However, Walt Jung and I did this 25 years ago, in preparation for our paper on Dielectric Absorption published in 'The Audio Amateur' and later in 'Hi Fi News'.
Yes, we listened to the SUBTRACTED difference between ceramic (and many other caps) by using Scott Wurcer's AD524 IN Amp (truly a breakthrough in its time).
What you are mostly hearing Jan, is DA, or LINEAR DISTORTION. It is out of time and level with the original, BUT it sounds like the original music.
There is a NON-LINEAR component in large value ceramic caps, but it isn't measured separately in this test. However, it can be measured separately by conventional methods.
Since, we can do this sort of test with analog methods, the digital approach, while having some advantages, HAS TO BE PRISTINE in order to really tell US much, that we don't already know.
This digital test is interesting, in principle, and someday it could become a formidable tool, when the computer A-D clock rate goes up significantly and more bits are added.
For example, as it happened to me 35 years ago: Limited bits won't tell us much, even though we had a HIGHER clock rate (50KHz) at the time than most people live with, today.
Yes, we listened to the SUBTRACTED difference between ceramic (and many other caps) by using Scott Wurcer's AD524 IN Amp (truly a breakthrough in its time).
What you are mostly hearing Jan, is DA, or LINEAR DISTORTION. It is out of time and level with the original, BUT it sounds like the original music.
There is a NON-LINEAR component in large value ceramic caps, but it isn't measured separately in this test. However, it can be measured separately by conventional methods.
Since, we can do this sort of test with analog methods, the digital approach, while having some advantages, HAS TO BE PRISTINE in order to really tell US much, that we don't already know.
This digital test is interesting, in principle, and someday it could become a formidable tool, when the computer A-D clock rate goes up significantly and more bits are added.
For example, as it happened to me 35 years ago: Limited bits won't tell us much, even though we had a HIGHER clock rate (50KHz) at the time than most people live with, today.
Speaking of audio quality, Scott. Did you design the AD811-829 series of video amps? Is there something about them that I should know about, when using them in an audio application? Their basic topology looks similar to the AD797, of course, but there may be significant differences that I don't know about.
john curl said:
Unless you have a very special definition of "linear distortion" (I would appreciate if you could be specific here), I disagree. DiffMaker should not let "linear distortions" through.
Whatever theory of DA you are using, DA is still a non-linear process. It's only that it could sometimes be linearized following a "small signal" pattern. Which doesn't mean what you hear at the DiffMaker output is "linear distortion", but only the result of a sensitive method to detect non-linearities.
Speaking of alcohol, Scott. Have you found a '2 buck Chuck' or its equivalent yet, now that the stock market has crashed, that tastes essentially the same, as those fine wines that you and SY like to drink so much? It is really the same thing as the audio quality problem.
john curl said:
Actually the topologies are not the same at all, the AD811 and AD829 are as simple as possible textbook current feedback and voltage feedback amplifiers.
Syn08, you don't know enough about DA, and you should do some comparison tests, yourself, before presuming anything. I have already done my homework.
john curl said:
I'm not sure what you mean. As Harry Pearson and others have pointed out wine and food anologies to audio fail. There is no reference standard, everyone has a different taste in food.
People get caught up in the same old "folks with more money than sense" stuff.
Well, Scott, you didn't answer my question. Aren't you interested in those big buck bottles of wine, just like SY? I am not a wine drinker, I can't afford it, and I hate the taste of cheap wine.
I find the same parallel to audio, in Cognac, whether you want to address it or not. I, frankly, hate the taste of cheap brandy, or brandy in general. Average Cognac is OK, but kind of expensive. I keep looking for the cheapest Cognac that I can drink, and not 'gag' due to the fact that my only steady income is social security. I just wondered if you found something useful in low cost wine tasting. It should be about the same, in my opinion, as finding low cost audio.
I find the same parallel to audio, in Cognac, whether you want to address it or not. I, frankly, hate the taste of cheap brandy, or brandy in general. Average Cognac is OK, but kind of expensive. I keep looking for the cheapest Cognac that I can drink, and not 'gag' due to the fact that my only steady income is social security. I just wondered if you found something useful in low cost wine tasting. It should be about the same, in my opinion, as finding low cost audio.
john curl said:
Nope, I don't bother much anymore. Actually it's a lot like the Toshiba FET's, the rich have depleted the stocks of old brandies used for blending and the result is a general decrease in quality across the board. My "Blowtorch" was a 1929 Late Bottled Grande Champagne Cognac from Berry Brothers and Rudd. Long gone.
OK, Scott, how about AD817,825,and 829? They have a similar 'equivalent circuit' to your AD797. Who designed these parts, if it isn't a company secret, or something?
john curl said:
So did I. I already pointed you to my Journal of Applied Physics work on this topic. And no, I did not do any subjective tests about.
So you'd better go and update/refresh your knowledge/understanding of DA. As usual, what you did 40 years ago is today mostly outdated, from both theoretical and practical perspectives.
scott wurcer said:
I can testify that Highland Park 12 y.o. (single malt Scotch) has dropped significantly in quality. They've come out with an 18 y.o., which I presume is taking up some of the whisky that would otherwise go into the 12 y.o. (The age being a minimum, 12 could--and did--contain older whisky as well as some that was strictly 12 years old.)
Grey
John: As I've said before, the wine analogy fails because anyone with even a small amount of experience can distinguish between Two Buck Chuck and Chateau Latour in a blind tasting. Not to say that she/he'll know which is which (though this is really pretty easy, much easier than an MW or MS or WSET wine certification blind test), but she/he will certainly distinguish them in a multiple trial triangle or ABX comparison. Anyone who judges a wine competition passes blind tests like that routinely.
When you can show that sort of distinguishable difference between your excellent Parasound preamp and your excellent Blowtorch, then I'm with you 100% on bringing wine or cars or whatever into the argument. Until then, my strong suspicion is that your low cost product is already far better than anyone can actually hear in a controlled side by side comparison.
When you can show that sort of distinguishable difference between your excellent Parasound preamp and your excellent Blowtorch, then I'm with you 100% on bringing wine or cars or whatever into the argument. Until then, my strong suspicion is that your low cost product is already far better than anyone can actually hear in a controlled side by side comparison.
GRollins said:
Not technically the same thing but the same principle. My theory is that the infrastructure could not take the hit of all the affluent boomers during the bubble. They took in as much money as they could and f* the future.
When it comes to DA, the best papers on it appear to be in the 1950's when analog computing was so prominent. Walt, Scott's and my work done 25 years ago, still holds up. There is really nothing newer or better that I have seen yet, and what is exasperating, is that I HAVE to go back 25 years, because that is when we addressed these problems. Most here are asking, and SLOWLY answering the SAME questions that we have already addressed.
DA is DA, and polystyrene is still better than MYLAR, even after 25 years. That is reality, fellow engineers.
DA is DA, and polystyrene is still better than MYLAR, even after 25 years. That is reality, fellow engineers.
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