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#41
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Does anyone know of this challenge?
Bromo wrote:
On 4/24/04 1:13 PM, in article cfxic.14174$0u6.2394685@attbi_s03, "Stewart Pinkerton" wrote: Given that the amplifiers' ability to drive difficult load is removed - then the challenge is removed quite effectively. Why? Where did you *ever* see a 'high end' maker claim that the 'superior' sound of his amp had anything to do with sheer power? Power into low impedance and low to no global feedback is what I hear from most amplifier advertisements. OK, so there is another possible differentiator that would be tested for validity: low/no global feedback vs normal global feedback. Wouldn't it be nice if we can settle the issue of whether low/no global feedback sounds any different? Oh, that and a DC to daylight flatness with low distortion. You clearly have not read ads of certain tube amps. |
#42
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Does anyone know of this challenge?
Then you are agreeing with the poster to whom you are responding and to
Clark, both say exactly what you are saying. Those not agreeing with you and Clark hold the view that "high end" amps have each an "sonic signature" by which identifying one from another is normal. You have spilled alot of ink, bandwith, to agree with those with whom you want to have a difference of opinion. The amp company was no doubt of the latter category,ie. their amps have a sound by which to identify it in a test using Clark's rules, he left with his money. AFAIK Clark brought the Challenge to a well known high-end amplifier company and left with his money. With those rules he is likely to keep it. Most amplifiers behavior into comression makes or breaks them! |
#43
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Does anyone know of this challenge?
"So I tend to agree with another poster, the test is quite meaningless.
If you want to buy an amp, you should not have to correct its frequency response due to its flaws. Better to buy an amp with no flaws." The ability to drive an extreme load at the edje of an amp's performance is not at issue. When an amp is driven into such a load and is overlaoded doesn't show a flaw, only that the load is outside it's performance design specs. The real test is for those claiming "night and day" obvious anyone can hear them differences between amps with similar performance specs. If one looks enough some condition can be so extreme so as to drive one amp into an unstable condition, that in this instance is irrelevant. It is a purchase consideration when an amp of x cost and another of 10x are found by test to sound no different. The same consideration would apply under the extreme conditions you propose, why buy the second amp if the first costs 1/10 the other and sounds the same under those conditions. |
#44
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Does anyone know of this challenge?
On 4/24/04 9:00 PM, in article H4Eic.16486$YP5.1208573@attbi_s02, "Nousaine"
wrote: Bromo wrote: On 4/24/04 1:10 PM, in article Acxic.14166$0u6.2392261@attbi_s03, "Nousaine" wrote: AFAIK Clark brought the Challenge to a well known high-end amplifier company and left with his money. With those rules he is likely to keep it. Most amplifiers behavior into comression makes or breaks them! Am I to take your point as meaning that an amplifier operating in its linear range will sound just like any other amplifier with similar frequency response? Not having measured or listened to but a dozen or so, I cannot say for sure, but on the ones I measured, save tubes which distort in a very melodic way throughout their range, I would agree. I would further say this is a silly non-contest. |
#45
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Does anyone know of this challenge?
On 4/24/04 1:03 PM, in article P5xic.20708$aQ6.1263449@attbi_s51, "Nousaine"
wrote: Given that the amplifiers' ability to drive difficult load is removed - then the challenge is removed quite effectively. Sure and how many "tough" loads are there? Stewart's speakers may qualify but of the hunreds of home speakers I've tested I can't recall a single one (including the 'stats) that would qualify as a difficult load to drive. Martin Logan has a 1 Ohm impedance at the high end. Apogees have a sub 1 Ohm impedance as well. Thiels are notorious for requiring a lo of current in the bass (and tend to be 3 Ohms) Magnepans are -- magnepans and then to have a sub 5 Ohm load. All of these are considered to be "difficult" to drive - and many integrated amp manufactuers place warnings on their amps to not have speakes with impedances that low! Many times in loud passages the amps could overheat and trip thei protection circuit - or in extreme cases with no protections, blow up! But, if you don't see it - feel free to take the "40Wpc into 8 Ohms at 1Khz" integrated and try to drive a Thiel 7.2.... It is true that many autosound enthusiasts like to wire multiple woofers, often with multiple coils, in ways that might qualify. But Richard Clark's challenge has put the amp sound for autosound to rest as well. He is trying to prove a negative, so the quest will be forever. This whole thing struck a nerve - people doing a flashy sort of thing by putting up a large sum of money with rules constructed so they won't ever be "wrong" The whole point of an amp is to source power - and matching that to the needs of the speaker for good sound reproduction is the big task for that link in the chain. This "challenge" has so many if's and conditionals, that it generated more heat and smoke than light. It is understood by anyone that if you do not feed the speaker with enough power, it won't sound good - too much power, and you will blow it out. Conventional measurements should indicate if the speaker is likely to be suitable, but to think we understand hearing and the processing our brains go through to change pressure to sound to make it an end game is pure arrogance to me! |
#46
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Does anyone know of this challenge?
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#48
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Does anyone know of this challenge?
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#49
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Does anyone know of this challenge?
On 4/24/04 9:00 PM, in article y4Eic.16484$YP5.1208556@attbi_s02,
" wrote: I think you have failed to grasp what the test is to exclude in amps. Exclude *what* in amps? For purposes of discussion let us say two amps from different companies are to be tested. One costs 1000 k and has performance and specs very similar to another at 10000k. The latter has been reviewed wherein it was said it had night and day differences in a list of sound qualties to which a list of common audio writing labels is attached. They said specifically the obvious difference was with comparsion to the first amp. Now we do the test and no one can pick the amps from another above the level of guessing alone. The test was to see if the percieved list of quality labels attached to the second but said to be missing in the first was an artifact of the perception process or inherent in the amps. The results suggest it was not in the amps. Because the performance specs were similar, the load into which they were driven was not a variable, only the claimed "night and day" differences. Both would agree that amp limiting was not in the picture. The contest is a silly endevour because of the various loads an amplifier is asked to drive into - each speaker is different in impedance and the amount of current required in order to get a nice, flat response out of it (or a response the listener finds to his or her liking). |
#50
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Does anyone know of this challenge?
On 4/24/04 9:00 PM, in article %4Eic.16489$YP5.1208529@attbi_s02, "Nousaine"
wrote: Suppose not if this is the sort of challenge that is put forth - remove any possible way of differentiating one amp from another then claim victory when you can't tell the difference! This tells me you really don't understand the high-end. All the factors that Clark includes in his prereqs are well known and well understood issues that when viewed as problems have been solved long ago. Fine - I must not "understand" - so enlighten me! The subjectivist crowd and the high-end, on the other hand, claim that there are "other" factors which cannot be measured with traditional tools that contribute to the sound of amplifiers. Clark's prereqs could not possibly rule out those factors as they are all standard things. I would concede that we do not have a full 100% understanding of all possible sonic differences. I do not need to offer $10k in a debunking escapade to realize that the world is not going to be black and white despite my earnest desire to try to force it there. I am an RF engineer by profession and training - and I have to figure out new ways to measure things all the time. Why should audio be different? Sure, there might be people that fool themselves into thinking that there is some ineffable difference between a Yamaha and a Halcro - and given the way this test is set up - it is skewed to prefer the Yamaha since the amplifiers aren't going to be driven into compression where any differences might be seen. If your conception of the "high end" is going on a debunking fest - I don't get it - and probably never will. |
#51
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Does anyone know of this challenge?
S888Wheel wrote:
From: chung Date: 4/24/2004 7:15 AM Pacific Standard Time Message-id: On the other hand, the high-enders' position is that there is something magical about the sound of expensive amps that cannot be quantized via measurements. That's what the challenge attempts to debunk. Why do objectivists continue to burn this straw man? I don't know any subjectivists who claim any "magic" is at work. Oh yeah? A casual search finds the following post: http://groups.google.com/groups?q=tu...y.edu&rnu m=3 Here's what Zipser said in that post: "Probably the one and only solid state amplifier line that sonically posseses the same magic as your tube amplifier is the PASS Labs Aleph series of amplifiers." There are many references to "tube magic"; just do a google search on the various audio newsgroups. BTW, you misunderstood what I said. I said that some high-enders believe there is something magical about the sound of certain highly touted amps. That does not mean that I am saying that subjectivists believe there is magic at work. It simply means that said high-enders cannot explain why these amps sound so great, since measurements do not explain such greatness. It seems like you are imagining a strawman being burned. When someone says that something sounds magical, do you always assume that someone is saying there is magic at work? |
#52
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Does anyone know of this challenge?
Bromo wrote:
On 4/24/04 2:31 PM, in article , " wrote: I agree about current limits being the real physical reasons an amp might sound different from another. But those advocating the inherent amp sound different view say that when with equal current capacity, amps will still sound different. Yes - this makes this sort f test rather useless in information or enlightenment. As compared to, say, a typical high-end review of an amp? I do not see how this "challenge" serves anyone but the ego of the "debunker"... Then, as many have already pointed out here, you don't understand why the challenge was laid down in the first place. It is a response to typical audiophile claims. -- -S. "They've got God on their side. All we've got is science and reason." -- Dawn Hulsey, Talent Director |
#53
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Does anyone know of this challenge?
Bromo wrote:
On 4/24/04 10:15 AM, in article , "chung" wrote: Realisticqlly an amp running out of power is the main reason one would her distortion vs. another amp. Given the power requirements across the frequency band would reveal the differences in the amps -- the challenge is a false challenge, then! So you think any two amps with similar output power measurements would sound the same? Works for me! Nope - you would have to measure distortion, intermod, channel separation, transient response, frequency response, and it is late I am sure I left something out.... So you just stated that there are differences that are in addition to the drive capabilities of the amps. So just insuring that two amps have similar drive capabilities does not insure that they sound the same. Therefore you just prove that the challenge is not faulty at all! On the other hand, the high-enders' position is that there is something magical about the sound of expensive amps that cannot be quantized via measurements. That's what the challenge attempts to debunk. I don't think it is a useful "challenge" - since you CANNOT divorce the needs of a particular speaker or transducer from this and still come up with anything useful to a consumer that I hope you are tring to "protect". Note that they are not saying that they will match the noise, distortion, interchannel effects, transient responses, etc. So if those things would differentiate amps, then the challenge is meaningful. For instance Halcro advertises a THD that is much lower than most other amplifiers at a power level not likely to ever be reached. Perhaps that is their edge in this game of diminishing returns. The Theta Drednaught II shows a great amount of frequency extension - and given that I have designed (RF) amps for the last 10 years, I can see a small amount of value for that if it is true. It means the source of distortion has been moved to the component feeding the amp. Even if it is overkill, this is a HOBBY, where the pursuit of perfection is part of the fun (the most fun being music). Question then is whether the Halcro can be differentiated from any other amp with the same drive capabilities and similar frequency response. The challenge can answer that. So, in your opinion, why would anyone buy a $10K 100W amp, when there are other 100W amps with low distortion available for $1K? I have no opinion - it depends upon the amp and the speaker. I have some Thield 2.4's and it required a fair amount of current to make the bass sound good. This made me seek out the best value to correct it given that I only had about 70-80Wpc. I ended up with a NAD S200 - which made the bass sound good without muddying the upper frequencies. I ended up paying more than $1k for it. (It was 225Wpc). If someone offers me a hand crafted piece of electronics, with a vanishingly low noise floor, low IMD and harmonics, incrementally better than your $1k amp, and wants to charge me $2-4k for it (more realistic) - I wouldn't fault him or her at all. Why should I? But don't you want to know if another amp with the same output drive as your NAD will sound the same? Maybe you don't, but the question is a meaningful one, and I fail to see why you think you know the answer before the test. |
#54
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#55
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Does anyone know of this challenge?
On 4/25/04 1:25 AM, in article ZYHic.26492$IW1.1268676@attbi_s52, "Nousaine"
wrote: Oh I get it. You have to have a DIY subwoofer like mine before amps ain't amps. There aren't currently any consumer passive (or even active) subwoofers that have response below 15 Hz. So the sub 20Hz distortion might not be an appropriate measure. The largest logical problem with "debunking" is that you are placing yourself in the position of proving a negative (that a SS amp does NOT have any differences) - and since all you can do is discredit (which is the idiot half brother of proper scientific light), we see all kinds of limited tests with "rewards" and "challenges" - but it beings us back to the problem of proving negatives. The time and effort might be spent a bit more productively - perhaps trying to research and measure all sources of sonic imperfections not already known - pushing the forefront of hearing sciences, and so on. |
#56
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Does anyone know of this challenge?
From: (Nousaine)
Date: 4/24/2004 10:25 PM Pacific Standard Time Message-id: ZYHic.26492$IW1.1268676@attbi_s52 (Thomas A) wrote: (Nousaine) wrote in message news:Acxic.14166$0u6.2392261@attbi_s03... wrote: Bromo wrote in message ....large snips...... This sounds like a bogus 'challenge' to me. There are more things, e,g, it cost 100-300 dollars and you need to be a subscriber of a car magazine or worker in car industry, as I understand it. The amp according to these rules must be a car amp. However, if I would do the challenge, I would seek up two amps with different HP filtering in the bass range (if such exist among car amps; there is nothing in the rules what I can see about the built in normal HP filtering of amps to avoid DC). Play the music to the film "Fifth Element" and use speakers with e.g. 10 x 15 inch woofers in a closed box system in a sealed small room. Play the song where there is a sweep going down to 5 Hz at loud volumes and try to "feel" the difference in the body. 1.5-3 dB difference in the 7-15 Hz region may be percieved differently. Challenge rules, see http://groups.google.com/groups?q=%2...enge+rules+gro up:rec.audio.car&hl=en&lr=&ie=UTF-8&oe=ISO-8859-1&group=rec.audio.car&selm =3ff8669c.126950265%40news.east.cox.net&rnum=6 AFAIK Clark brought the Challenge to a well known high-end amplifier company and left with his money. Just a note, I would say that at least 50% of the amps fails to be completely transparent in tests made by the Swedish Acoustical Society. The use before/after listning tests, blind, with bass-heavy music (down to 5 Hz signals). These flaws would probably never be detected in "normal" speaker systems, e.g. B/W 801. T Oh I get it. You have to have a DIY subwoofer like mine before amps ain't amps. There aren't currently any consumer passive (or even active) subwoofers that have response below 15 Hz. And here, Mr Wheeler says that a 10 Hz subwoofer is "useless." Maybe that's why the high-end can't prove that amps ain't amps ..... none of them have a subwoofer with adequate bandwidth. Indeed most of them don't have subwoofers at all. They're too "slow" and the bass stays in the room so you get to hear/feel it. The fast-bass sneaks out too quickly. Please try to get your facts straight. I said a 6hz tone is useless in highend. I still say it's useless for me. I guess Tom finds some use for it. There are plenty of speakers with adequate bandwidth for the purpose of playing music. Many of us are not interested in reproducing train wrecks and damaging the structures of our homes. |
#57
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#58
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Does anyone know of this challenge?
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#59
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Does anyone know of this challenge?
From: chung
Date: 4/24/2004 10:28 PM Pacific Standard Time Message-id: M%Hic.17630$YP5.1284125@attbi_s02 S888Wheel wrote: From: chung Date: 4/24/2004 7:15 AM Pacific Standard Time Message-id: On the other hand, the high-enders' position is that there is something magical about the sound of expensive amps that cannot be quantized via measurements. That's what the challenge attempts to debunk. Why do objectivists continue to burn this straw man? I don't know any subjectivists who claim any "magic" is at work. Oh yeah? A casual search finds the following post: http://groups.google.com/groups?q=tu...o.high-end&hl= en&lr=&ie=UTF-8&oe=UTF-8&group=rec.audio.high-end&selm=7mu81k%246gr%241%40 agate.berkeley.edu&rnum=3 Here's what Zipser said in that post: "Probably the one and only solid state amplifier line that sonically posseses the same magic as your tube amplifier is the PASS Labs Aleph series of amplifiers." There are many references to "tube magic"; just do a google search on the various audio newsgroups. Obviously figurative speech refering to a prefered sound from tubes. Hardly a claim of the paranormal. BTW, you misunderstood what I said. I said that some high-enders believe there is something magical about the sound of certain highly touted amps. Well please clarify what you are saying. Are you complaining about figurative speech or are you complaining about claims of paranormal activity? That does not mean that I am saying that subjectivists believe there is magic at work. It did seem like you were. It simply means that said high-enders cannot explain why these amps sound so great, since measurements do not explain such greatness. So? Many people cannot explain many things they enjoy in life. That fact per se does not mean they are making claims of paranormal experiences. It seems like you are imagining a strawman being burned. When someone says that something sounds magical, do you always assume that someone is saying there is magic at work? It is not like such straw men have never been burned in the past by objectvists. If you are complaining about hyperbole fine. It didn't look that way to me. It looked like you were trying to tar and feather subjectivists as believers in the paranormal. While I am sure many are, I am even more sure that some are not. And the same is true for objectivists. |
#60
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Does anyone know of this challenge?
On 4/25/04 10:13 AM, in article , "Steven
Sullivan" wrote: Bromo wrote: On 4/24/04 2:31 PM, in article , " wrote: I agree about current limits being the real physical reasons an amp might sound different from another. But those advocating the inherent amp sound different view say that when with equal current capacity, amps will still sound different. Yes - this makes this sort f test rather useless in information or enlightenment. As compared to, say, a typical high-end review of an amp? The point here is how this "challenge"/test is supposed to enlighten - to point out that it might be uninformative and might steer people into wasting money as a poorly written and analyzed review might be - isn't the "challenge" supposed to be better than that and serve the general enlightenment of people in general? If it is no better than the 'high end reviews' you are disparaging, it is adding to the much in high end rather than trying to sort things out. It really bothers me that the results of this might cause people to inappropriately pair inefficient speakers with amps incapable of driving them. (BTW, I happen to like the subjectivist reviews, myself, as I have noticed differences in a entire system with different amplification - which I am convinced have as much to do with the speaker-amp interaction as anything else.) I do not see how this "challenge" serves anyone but the ego of the "debunker"... Then, as many have already pointed out here, you don't understand why the challenge was laid down in the first place. It is a response to typical audiophile claims. I do know why it was laid down - I am questioning its value in discrediting the marketing departments of high end audio firms' employ, since it risks, through its own hype, of throwing out some other more important truths, too. |
#61
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Does anyone know of this challenge?
Stewart Pinkerton wrote:
On 24 Apr 2004 15:24:40 GMT, (Thomas A) wrote: However, if I would do the challenge, I would seek up two amps with different HP filtering in the bass range (if such exist among car amps; there is nothing in the rules what I can see about the built in normal HP filtering of amps to avoid DC). Play the music to the film "Fifth Element" and use speakers with e.g. 10 x 15 inch woofers in a closed box system in a sealed small room. Play the song where there is a sweep going down to 5 Hz at loud volumes and try to "feel" the difference in the body. 1.5-3 dB difference in the 7-15 Hz region may be percieved differently. Challenge rules, see http://groups.google.com/groups?q=%2...cox.net&rnum=6 Unfortunately, you failed to notice that in test condition no. 5, Richard is allowed to EQ the amps to have the same frequency response, negating this kind of cheap shot. FWIW I found Clark's challenge and some of his replies to criticisms, here http://www.talkaudio.co.uk/vbb/showt...threadid=18815 And alas it doesn't seem unusual for critics to have not actually read the terms of the challenge (though that doesnt' stop them from making erroneous claims about it!) http://www.soundandvisionmag.com/idealbb/view.asp?topicID=31069&forumID=29&catID=1&search=1 &searchstring=&sessionID={14295840-707C-4B98-9F45-636A9838AAAE} -- -S. "They've got God on their side. All we've got is science and reason." -- Dawn Hulsey, Talent Director |
#62
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Does anyone know of this challenge?
Bromo wrote:
On 4/24/04 9:00 PM, in article %4Eic.16489$YP5.1208529@attbi_s02, "Nousaine" Sure, there might be people that fool themselves into thinking that there is some ineffable difference between a Yamaha and a Halcro - Alas, not *might*. It's taken as a *given* by audiophile culture. If you're unaware of such prejudices existing in audiophilia, then you can't understand the background that produced Clark's challenge. -- -S. "They've got God on their side. All we've got is science and reason." -- Dawn Hulsey, Talent Director |
#63
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Does anyone know of this challenge?
On 24 Apr 2004 18:35:33 GMT, Bromo wrote:
On 4/24/04 1:13 PM, in article cfxic.14174$0u6.2394685@attbi_s03, "Stewart Pinkerton" wrote: Given that the amplifiers' ability to drive difficult load is removed - then the challenge is removed quite effectively. Why? Where did you *ever* see a 'high end' maker claim that the 'superior' sound of his amp had anything to do with sheer power? Power into low impedance and low to no global feedback is what I hear from most amplifier advertisements. Oh, that and a DC to daylight flatness with low distortion. You will *never* see 'DC to blue light' and no global feedback mentioned in connection with the same amplifier. You'll also not see ability into low loads mentioned for anything but Krell and H-K. You *will* see technobable like 'microdynamics' and 'soundstaging' bandied about by ragazine reviewers - who will *never* submit to DBTs. My Krell will drive a 1-ohm load continuously, but that has nothing to do with how it *sounds* on normal speakers. The point is that how it can source a 1 ohm current load means you aren't restricted to 'normal' speakers (whatever those are) - and if there is a ton of current required - you have it without the amplifier going into some sort of foldback. Which has what exactly to do with any notion of 'superior sound' into normal speakers? You seem to have completely missed the claimed point of 'high end' amplifiers. Please note that I agree with your point of view, it's just that you seem to have stepped into a debate with no actual conception of one side of it. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#64
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On Sat, 24 Apr 2004 23:47:07 GMT, (S888Wheel) wrote:
From: chung Date: 4/24/2004 7:15 AM Pacific Standard Time Message-id: On the other hand, the high-enders' position is that there is something magical about the sound of expensive amps that cannot be quantized via measurements. That's what the challenge attempts to debunk. Why do objectivists continue to burn this straw man? I don't know any subjectivists who claim any "magic" is at work. But you *do* know lots of subjectivists who claim that a 'high end' amp has obvious and easily audible differences from a 'mid-fi' amp, do you not? No matter what technobabble term is claimed as the mechanism, it's basically all just 'magic' which is claimed to cause the difference in sound - which does not of course exist in the physical world. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#66
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#67
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Does anyone know of this challenge?
On Sun, 25 Apr 2004 05:13:36 GMT, Bromo wrote:
On 4/24/04 10:15 AM, in article , "chung" wrote: So, in your opinion, why would anyone buy a $10K 100W amp, when there are other 100W amps with low distortion available for $1K? I have no opinion - it depends upon the amp and the speaker. I have some Thield 2.4's and it required a fair amount of current to make the bass sound good. This made me seek out the best value to correct it given that I only had about 70-80Wpc. I ended up with a NAD S200 - which made the bass sound good without muddying the upper frequencies. I ended up paying more than $1k for it. (It was 225Wpc). If someone offers me a hand crafted piece of electronics, with a vanishingly low noise floor, low IMD and harmonics, incrementally better than your $1k amp, and wants to charge me $2-4k for it (more realistic) - I wouldn't fault him or her at all. Why should I? That's not the point. There are many so-called 'high end' manufacturers charging $10-20k for amplifiers which are *less* capable than your S200 (virtually all the tube ones, for a start). Further, what's the point of vanishingly low noise and artifacts, when such a device doesn't *sound* any different from your NAD? Forget 'high end' amps, they are mere conceits - spend the money on better speakers - such as CS7.2s! -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#68
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On Sun, 25 Apr 2004 05:10:54 GMT, Bromo wrote:
On 4/24/04 1:03 PM, in article P5xic.20708$aQ6.1263449@attbi_s51, "Nousaine" wrote: Given that the amplifiers' ability to drive difficult load is removed - then the challenge is removed quite effectively. Sure and how many "tough" loads are there? Stewart's speakers may qualify but of the hunreds of home speakers I've tested I can't recall a single one (including the 'stats) that would qualify as a difficult load to drive. Martin Logan has a 1 Ohm impedance at the high end. Where there is virtually no power to be delivered to the speakers. I've not found M-Ls to be particularly amplifier fussy. Apogees have a sub 1 Ohm impedance as well. Only one model - the old Scintilla. All others have a mostly resistive 3-4 ohms impedance, but they do like lots of power as they're not very sensitive. Thiels are notorious for requiring a lo of current in the bass (and tend to be 3 Ohms) Indeed yes, but they're quite sensitive in the main, so a good 60-watter will generally do - and that's about the easiest size of amp to design. Magnepans are -- magnepans and then to have a sub 5 Ohm load. Any half-decent amp should drive a 4-5 ohm load without problems, it then just becomes a matter of how loud you want to play. All of these are considered to be "difficult" to drive - and many integrated amp manufactuers place warnings on their amps to not have speakes with impedances that low! I have not seen *any* respectable integrated amp (I'm not talking about cheap receivers or surround-sound amps) which warns against 4 ohm loads. The decent ones such as Arcam are perfectly capable of driving 2-ohm loads. Many times in loud passages the amps could overheat and trip thei protection circuit - or in extreme cases with no protections, blow up! You must have different experience to mine regarding what any reasonable person would call 'hi-fi' equipment. But, if you don't see it - feel free to take the "40Wpc into 8 Ohms at 1Khz" integrated and try to drive a Thiel 7.2.... No reasonable person would try such a thing. What is your point? It is true that many autosound enthusiasts like to wire multiple woofers, often with multiple coils, in ways that might qualify. But Richard Clark's challenge has put the amp sound for autosound to rest as well. He is trying to prove a negative, so the quest will be forever. This whole thing struck a nerve - people doing a flashy sort of thing by putting up a large sum of money with rules constructed so they won't ever be "wrong" Tell that to the 'high enders' who claim that say a Pass Labs Aleph 1.2 at ÂŁ12,000 will sound 'obviously, night and day' different from a $500 Yamaha AX-592. They have similar power capability, but claims made for 'sound quality' are very different! -- Stewart Pinkerton | Music is Art - Audio is Engineering |
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Bromo wrote:
On 4/25/04 10:14 AM, in article , "chung" wrote: So you think any two amps with similar output power measurements would sound the same? Works for me! Nope - you would have to measure distortion, intermod, channel separation, transient response, frequency response, and it is late I am sure I left something out.... So you just stated that there are differences that are in addition to the drive capabilities of the amps. So just insuring that two amps have similar drive capabilities does not insure that they sound the same. Therefore you just prove that the challenge is not faulty at all! The challenge is faulty for the following reasons: 1. You are stuck with that guys' speakers - bad sounding speakers will mask an amps sound. So you are now saying that the test is not faulty if you can use your own speakers? For your own buying decision, that is a reasonable stipulation. And maybe that guy would even agree to use your own speakers if you bring them along. But how do you know "bad sounding speakers" are being used in the test? For the general question of what makes amps sound different, I don't see any problem with using a pair of speakers that have reasonable performance. As long as the identity of the speakers is revealed, that is still a valid test. I don't see any ads of expensive amps that have a condition that only certain speakers have to be used for it to sound great. 2. The person will equalize his amplifier - since his amplifier has sound qualities he has to equalize to sound flat. Like you said in a previous post, the majority of solid state amps have flat frequency response. So I don't see why that is a big concern. If you leave out that condition, then the test is truly meaningless, since you can simply put a resistor in series with the output and achieve a very different sound, since you have messed up the frequency response. In any event, isn't it nice to know that if two amps have similar frequency responses, then they sound the same? That's why the challenge is interesting, and potentially very useful to consumers. |
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S888Wheel wrote:
BTW, you misunderstood what I said. I said that some high-enders believe there is something magical about the sound of certain highly touted amps. Well please clarify what you are saying. Are you complaining about figurative speech or are you complaining about claims of paranormal activity? It really speaks volumes about how you are preconditioned to read certain posts from the non-subjectivist side. I was not complaining about anything at all, and yet you took it that I was. |
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OK, so there is another possible differentiator that would be
tested for validity: low/no global feedback vs normal global feedback. Wouldn't it be nice if we can settle the issue of whether low/no global feedback sounds any different? It won't be settled - you cannot prove a negative. "It's true that absence of evidence is not evidence of absence, but it would be churlish to ignore the data." Norm Strong |
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On 4/25/04 1:38 PM, in article 7ISic.32063$w96.2204064@attbi_s54, "Stewart
Pinkerton" wrote: But, if you don't see it - feel free to take the "40Wpc into 8 Ohms at 1Khz" integrated and try to drive a Thiel 7.2.... No reasonable person would try such a thing. What is your point? The point I was making is that the "challenge" when hyped (a $10k "prize is hype in this case) might make an average consumer think that any old amp low, mid or hi-fi was capable of driving any old speaker because "they sound the same." I have an AVR200 that used to drive my Thiel 2.4's - I now use a NADS200 to do the same - the articulation and bass response improved noticably due to the power - and according to the data sheet I had up to 90W available to do that (1kHz at 4Ohms was supposed to be 140W). The extra current really helped the sound I figure when driving that speaker. Made a difference, when I expected very little. |
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On 4/25/04 1:34 PM, in article AESic.32031$w96.2201891@attbi_s54, "Steven
Sullivan" wrote: Bromo wrote: On 4/24/04 9:00 PM, in article %4Eic.16489$YP5.1208529@attbi_s02, "Nousaine" Sure, there might be people that fool themselves into thinking that there is some ineffable difference between a Yamaha and a Halcro - Alas, not *might*. It's taken as a *given* by audiophile culture. If you're unaware of such prejudices existing in audiophilia, then you can't understand the background that produced Clark's challenge. I do know of all the marketing BS that goes on in this hobby. I am looking at a Halcro Ad on this month's Stereophile (pg. 15, May '04) right now. They have a bunch of gushing - nothing too much other than typical hype. Their claims are easily verifiable - a low IMD, so low you can't measure it. The most accurate and quietest phono stage available. You could compare their response to the ideal RIAA curve and measure the IMD at full power. If you measure any deviation in the RIAA curve, or any IMD's - you have caught them in a lie and you can feel confident in debunking them. I only say this because it would be easy to disprove this or verify it - rather than have a rather complicated and limited "challenge" to prove a negative. I also think that Sensible Sound tends to have a good "Skeptimania" columns as well, showing the BS laden traps some can find themselves in. Now, where did I put those battery "enhanced" Audioquest cables ..... :-) |
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Bromo wrote:
It won't be settled - you cannot prove a negative. In an absolute sense, of course. But, in a probabilistic perspective, one can sensibly conclude that something is very unlikely. |
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chung wrong:
S888Wheel wrote: From: chung Date: 4/24/2004 7:15 AM Pacific Standard Time Message-id: On the other hand, the high-enders' position is that there is something magical about the sound of expensive amps that cannot be quantized via measurements. That's what the challenge attempts to debunk. Why do objectivists continue to burn this straw man? I don't know any subjectivists who claim any "magic" is at work. Oh yeah? A casual search finds the following post: http://groups.google.com/groups?q=tu...o.high-end&hl= en&lr=&ie=UTF-8&oe=UTF-8&group=rec.audio.high-end&selm=7mu81k%246gr%241%40 agate.berkeley.edu&rnum=3 Here's what Zipser said in that post: "Probably the one and only solid state amplifier line that sonically posseses the same magic as your tube amplifier is the PASS Labs Aleph series of amplifiers." There are many references to "tube magic"; just do a google search on the various audio newsgroups. Holy cow. This means that Steve Maki's Yamaha Integrated amplifier must have 'tube magic' too .....Steve Zipser proved it sounded exactly like his Pass Aleph monoblocks driving those huge Dunlavy towers. That darned Yamaha sounds exactly like my Parasound integrated amps and my Brystons and the 5000 Watt Crown. So they must also have "tube magic." Oh! The shame of it all. BTW, you misunderstood what I said. I said that some high-enders believe there is something magical about the sound of certain highly touted amps. That does not mean that I am saying that subjectivists believe there is magic at work. It simply means that said high-enders cannot explain why these amps sound so great, since measurements do not explain such greatness. It seems like you are imagining a strawman being burned. When someone says that something sounds magical, do you always assume that someone is saying there is magic at work? I have always loved the smell of smoke. |
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Bromo wrote:
On 4/24/04 11:22 PM, in article , "chung" wrote: Bromo wrote: On 4/24/04 1:13 PM, in article cfxic.14174$0u6.2394685@attbi_s03, "Stewart Pinkerton" wrote: Given that the amplifiers' ability to drive difficult load is removed - then the challenge is removed quite effectively. Why? Where did you *ever* see a 'high end' maker claim that the 'superior' sound of his amp had anything to do with sheer power? Power into low impedance and low to no global feedback is what I hear from most amplifier advertisements. OK, so there is another possible differentiator that would be tested for validity: low/no global feedback vs normal global feedback. Wouldn't it be nice if we can settle the issue of whether low/no global feedback sounds any different? It won't be settled - you cannot prove a negative. So your real concern with any test is that it does not prove the negative? How about if you are the testee, and you cannot tell the difference. Is that good enough for *you*? While it may not constitute proof to you, to the rest of us if there is no audible difference between 2 amps with vastly different amounts of global feedback, then it certainly greatly reduces the significance of the low/no global feedback claims. As an engineer, aren't you curious to find out how the amount of overall feedback affects the sound? |
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Bromo wrote:
On 4/25/04 12:03 PM, in article , "S888Wheel" wrote: Please try to get your facts straight. I said a 6hz tone is useless in highend. I still say it's useless for me. I guess Tom finds some use for it. There are plenty of speakers with adequate bandwidth for the purpose of playing music. Many of us are not interested in reproducing train wrecks and damaging the structures of our homes. Speaking of this - in signal envelope and transients - would the 6Hz performance be important in an amplifier? I mean, a sharp rising tone might have a 6Hz component - would it be reflected in this or is there something else in the amp that would help with signal envelope and transient behavior? I'm surprised that as an RF engineer you do not see this. A sharp rising tone will have the higher frequency components. A 6 Hz tone is a really slow component in the signal. In a minimum-phase system like a power amp, there is a direct correspondence between frequency response and time-domain response. You don't have to ask about transient behavior, unless you are worrying about slew-rates, or other very large signal effects. If the rest of the system (the source recording, the CD player, the preamp, the speakers, etc.) cannot reproduce the 6Hz tones, then it makes no difference whether the amp can do that or not. If the rest of the system can reproduce the 6 Hz tones, and you are interested in listening/feeling it, then of course you want a power amp that reproduces 6 Hz. That pretty much eliminates all tube amps, and vinyl systems, by the way. |
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On 25 Apr 2004 14:15:44 GMT, Bromo wrote:
The time and effort might be spent a bit more productively - perhaps trying to research and measure all sources of sonic imperfections not already known - pushing the forefront of hearing sciences, and so on. Actually, since we can already prove that dozens of amplifiers sound exactly the same below the clipping point, the time and effort would most definitely be better spent in selecting better speakers, and placing them in the best position in a well-sorted room. Of course, this would destroy 90% of 'high end' mythology - but perhaps the world would be a better place for that............ -- Stewart Pinkerton | Music is Art - Audio is Engineering |
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On Sun, 25 Apr 2004 17:35:09 GMT, Bromo wrote:
Wouldn't it be nice if we can settle the issue of whether low/no global feedback sounds any different? It won't be settled - you cannot prove a negative. You can however prove that there is *zero* evidence on one side, and lots of evidence on the other side. Where would *you* place your bet? -- Stewart Pinkerton | Music is Art - Audio is Engineering |
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