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In Reply to: RE: Measurement and Perception and the Value of Each (Long Post) posted by jrlaudio on November 03, 2012 at 01:46:42
“I would like to discuss the reason why measurement exists and how & why this technique has been virtually thrown away in the hi-end world.”
I wouldn’t say it was “thrown away”........ Some measurements are very relevant.
“Perception is not a purely human thing. Dogs see colors, but not like we do. Their perception is different. Dogs would (if they could) say that certain colors do not exist. Does this preclude then that in a dogs world these colors do not exist? In terms of perception they do not exist for a dog. For humans the perception is different. We see more colors.”
If people could not see, they might believe that nothing travels faster than the speed of sound.................
“In sound, the dog might aurally perceive an extreme high-frequency capability (above 18kHz for instance) in one loudspeaker and virtually none in another. To our perception there is no high frequency capability or even a difference at all. Our perception at those frequencies does not exist. However does this preclude that those frequencies are not present? Of course not, we simply cannot perceive them.”
Nobody in the audio realm has ever believed that frequencies above 18 kHz do not exist. There is too much evidence to the contrary.
“Human perception via senses are limited. Both in terms of degree and especially in quantification ability. Because of this academia & sciences developed empirical measurement techniques to quantify aspects of phenomenon normally observed by human perception but were difficult to quantify. As electronics developed, devices came available to measure all aspects of the specific applications being explored.”
*All* aspects? That’s a leap of faith............................
“The degree to which measurement can perceive differences in audio characteristics has developed to an extreme level.”
I guess it depends what one defines as “extreme”..............
“It can discern minute difference in most parameters and at a degree of resolution far beyond human perception.”
Could it discern, for example, a violin solo by Jascha Heifetz from one by Itzhak Perlman?
I think I can do that with at least 90 percent accuracy, but I doubt any machine is capable of doing that.
Same goes for a piano performance by Vladimir Horowitz versus one by Martha Argerich.
“However, it appears that human arrogance (and I do not think that is too strong of a word) has thrown aside this fact.”
It is one thing to point out acts of arrogance, but it is dangerous to presume it where it's not obviously present.............
“I believe in the audiophile world many have, as a good friend of mine likes to say, ‘drank the Kool-aid’ being served up buy those who profit from this market.”
Who exactly serves up this “Kool-Aid?”
“Let me give you an example. (Yes ... I'm going there). When I attended Rensselaer College and later MIT many a moon ago, we began hearing about the use of OFC copper in audio cables. We were familiar with this cable, since OFC copper cable was developed at MIT for the purpose of reducing oxidation at joints and within cable bundles for the aerospace industry (specifically for cables for the then new Boeing 747). OFC wire was designed to reduce this self-oxidation to improve reliability & safety. Nothing more. However, the application to cables for audio was never part of the original design criteria for OFC wire. Actually oxygen-free copper has been around for a long time, but using it in wire didn't become marketable or necessary until the Boeing specification was proposed.”
This is fallacy. I happen to be an aerospace engineer, and am deeply familiar with electronics hardware. OFC means “oxygen free” at the time of manufacture. It does not imply it’s immune to oxidation. Aircraft wiring is not OFC, but silver-plated copper, in order to sustain conductivity. (The silver plating still oxidizes, but unlike OFC, won’t lose conductivity over time.)
“So, as good little audio research scientists, we began to see if we could quantify the claims being made by several new audiophile cable manufacturers (who shall remain nameless). We already new that "skin effect" issues were of course non-existent at audio frequencies. It has been well documented for about 60 years that skin effect does not occur until you reach a frequency of about 65kHz. It is observable and measurable. So we knew to discount this claim as bogus. When we began taking measurements of all known measurable electrical and acoustical properties when comparing OFC to normal high purity copper we found absolutely no measurable difference. Now understand this is no measurable difference at a degree of resolution far beyond that which is perceivable by human hearing.”
Whether skin effect is audible has not been proven unequivocally either way......... The debate kind of faded from existence during the digital age, because audibility of artifacts above 20 kHz became a non-issue, due to the CD being band-limited to 22 kHz.
“However, the OFC copper did not oxidize as quickly.”
But it still oxidizes..............
“But conversely, the oxidation on the outer surface of the wire also did not impede or effect the test measurements.”
Well if it’s aircraft wire, the reason is because it’s silver plated. Silver oxide has good conductivity relative to copper oxidation.
“It did however change things on crimped connections, particularly on micro-resistance values at the transition point of contact from wire to connector.”
That’s because the crimps fractured through the silver plating into the copper, exposing the copper to oxidation.
“In our tests we measured parameters like capacitance, inductance, inherent impedances at various audio frequencies and beyond, velocity factors, damping, current handling differentials, to name just a few. We were most interested in the aspects of time differentials in relation to frequency as claimed by these manufacturers. We found that velocity factors were not effected by OFC.”
I don’t think anybody claimed so. It’s more due to the surrounding insulative/dielectric material.
“We also found that in these ‘special’ cables the velocity factors for the separate windings allegedly carrying different frequencies were the same, therefore no ‘time correction’ was actually occurring as claimed.”
Once again, this is inconclusive.
“What we did find was significant variables in basic parameters like capacitance and inductance, within the various layers of this particular cable. In one case we measured what was in affect a RCL filter being created by the cable. It actually was producing a bandpass filter which was reducing a specific frequency and some harmonics. It was essentially, changing the response of the cable away from being flat. So here I make my point ...”
Nothing ground-breaking here...........
“Measurement allows us to learn the truth, in quantifiable terms about what we can and cannot perceive. However, perception and taste can at times be at odds with this. Why? It's a matter of what one wants.”
I personally think a product that sounds good should also measure well. But whatever someone likes, that’s his business. Even if it does NOT measure well.
“A person may want a sound system that reproduces with the greatest accuracy what is on the source material. Others may prefer to deviate from this to produce an aural aesthetic suited to their taste. A ‘warm tubey sound’ for instance. And you know what ... That's OK.”
At least you acknowledge that.
“However, let me give you a lesson in what thinking is going on the industry that builds this stuff. They think most audiophiles are sheep. I left the hi-end audio business for this reason. As a design engineer for a very well known amplifier manufacturer, I got sickened by the ‘audiophools’ comments,”
I think you’re “sickened” because you WANT to be “sickened”..........
“and marketing driven design assignments, and the way pricing was being developed.”
Should that be your problem?
“Hearing a discussion about how to increase base margins from 1000% to 2000%, as one example.”
That should be cited at face value.
“And this was in the 80's! Now you can buy a $50,000 pair of speaker cable. Ludicrous! Snake oil! There is no manufacturing process, material cost, development cost or anything in engineering that could cause a cable to have to be sold for that price. It is purely profiteering. This is fact.”
I’d be curious what this $50,000 cable is.......... (NBS makes some expensive cable, but I don’t think that expensive.)
“Now I come to what motivated me to post on AA after all these years. I recently was given a pair of these $50,000 speaker cables by a women who's husband died. A windfall? Ha! Well guess what ... I took a knife to them.”
I guess if one is independently wealthy (or purchased the cable at an extreme cut rate), he can do that..............
“They cost me nothing and I wasn't going to pawn them off to some schmuck who worships this stuff.”
How noble of you......... You could have sold it cheap, you know.
“That would be hypocritical of me.”
Not if you sold it cheap...............
“But I was curious about what proprietary engineering was justifing these prices, if any. So I cut them open. Removed the beautiful weaving of the outside, pulled back the poly jacket. What I found was shocking. I found a standard Belden branded communications multi-wire underneath. They didn't even get Belden to OEM the cable and not label it. After all, who would cut up a $50,000 cable and find this out?”
This would be grounds for a lawsuit, wouldn’t you think? (Provided your story was true.)
Do you have pics of this? That would really be revelatory.
“Certainly none of the magazines these days, that's for sure. (I miss Audio Magazine). This Belden wire is a cable that sells for about $2.53 per foot from Mouser.”
What was the Belden part number? Maybe it’s a good alternative to audiophile wire.
“When I priced everything out the cable cost about $270 to make, at retail prices mind you. There was nothing proprietary in this cable and all of the components making it up can be purchased online. They did use an exothermically welded connection on the spades, but other than that nothing out of the ordinary.”
You should have investigated if this measures better than soldered connections...... ;-]
“So how do they justify the price? First by wonderfully talented marketing, maneuvering good mag reviews, techno-babble, and a good dealer network.”
A $50,000 pair of speaker cables wouldn’t have much of a dealer network..............
“It is amazing how this alone can change perception while listening.”
I don’t know..... I’ve heard quite a bit of expensive stuff that didn’t impress me..........
“And BTW, before ripping apart this cable I put a load on it, swept it and measured the frequency and phase response. It was all over the place. The cable certainly would have sounded unique, but it did not pass the signal accurately. In fact, it greatly distorted the signal both in terms of phase and amplitude response and even exhibited IM artifacts as a result, much like vacuum tubes do.”
Most cables, regardless of price, do rather well in IMD testing..............
“It probably sounded very warm as a result. However was it ‘accurate’ or ‘transparent’ or ‘virtually invisible to the music’, as claimed? Not even close. But it probably sounded nice and warm. Did I say that already?”
“Probably?”.... You sure it sounded “warm?” [-;
“The point being, if you are looking for accurate, most and I mean most Hi-end audio equipment is not actually designed to that end.”
I’ve stated numerous times, nobody has agreed to a set of aural parameters that definitively define “accurate”. One man’s “accuracy” could be another man’s “inaccuracy”.
“If you measure things, as I have over the last 30 years, you discover this to be true. But if you don't really care about hearing the music as recorded and want to create an aural aesthetic to your own personal taste, you are in good company. You just need to be willing to pay the price to the snake-oil man just to develop that aesthetic.”
Heck, if you’d only reveal the Belden product, we can do the “snake oil” for cheap..... ;-p
“In conclusion, if you do the measurements you find two facts.
“1. Accuracy is cheaper.”
Once again, nobody knows at true accuracy really is.
“2. Distortion (of facts, physics and sound) is expensive.”
Not if you reveal the parts to make the expensive stuff..............
“So what do you think. Is creating your own aural aesthetic justification enough for the prices you are forced to pay?”
People buy what they buy. It’s not your or my business.
“What's your experiences with measurement?”
I’ve measured things too....... For about 30 years...... Unless it’s basic frequency response, most measurements really don’t tell the whole story.
“Are you of the belief that human hearing is far better than measurement?”
As long as a machine is unable to distinguish Heifatz from Perlman, my answer would be “Yes!”
“Do you believe in angels?”
Anaheim’s baseball team?
“Is global warming real? Hehe.”
Those of liberal political persuasion think it is........... I personally haven’t seen any objective evidence.
“You know what I mean. Are the manufacturers engineers or master marketeers or modern day magicians?”
You give them too much credit.
“How much Mrytlewood have you bought?”
None. But some audiophiles do have a wife to please.
Follow Ups:
Its very simplistic to pick away at this point by point and take things out of context. I never said machines can interpret music. What I said is an electronic device can resolve electronic values better than human hearing or other senses. We are dealing with electronics and signals, not music emanating from an instrument in an acoustic environemnt, a live sound. And this electronics is not involved in the creative process of creating or interpreting music itself. Electronics is used to record and replay music, within the degree it can do such things. However to subjectivly interpret the workings of electronics in the same way we listen to a violin in a concert hall is not only misplaced, but ineffective. If one was to "tune up" and electronic device by ear and sell it there would be so much variation from piece to piece nobody would buy it. Its function must be precisely measured by others of it kind; electronic devices. Just like only humans can interpret and apprieciate the music created by other humans.Even piano tuners use electronic devices to get a more precise tuning initially, then and only then detune for timbral human preference. The note A is precisely defined as 440hz and only a very rare few can tune to within a cent or so of that without some basis of comparative pitch, that's why tuning forks exist. One can get close, one out of millions can get it right on without a standard comparitive pitch. Now we use electronics to have this standard. Otherwise, instruments would be out of pitch relatively. Now I have worked with symphonic orchestras as well as pop musiciains and all use some device as a standard, either a tuning fork, a piano to tune to or an electronic pitch standard. The human ear is not precise enough for the intial pitch. ALL calibrated electronic devices and tuning forks are exactly on pitch; exactly vibrating or oscillating at 440.000hz. Humans can only distinguish in mid-frequencies (specifically 440hz) about 1/12 semitone change, which is about .037hz This is known as the "Just-Noticeable Difference". (See work by Rossing, Moore, and Wheeler) All electronic measurement devices can detect or produce frequency at resolutions as low as .001hz (or lower depending on clock accuracy). I would be more inclined to beleive a spectrum analysers output results for flat frequency response then depend on mine nor anyone elses ears to tell whether a loudspeaker has a flat response (necessary for accurate reproduction) or whether phase anomalies exist. (Let me say this, if a loudspeaker isn't flat it is adding timbral influence to the music that isn't on the recording. I want to hear the music, not the speaker)
Instruments not tuned a standard pitch reference was Mozart's biggest pet peeve. It is reported he had perfect pitch, and was always frustrated when a tuning fork wasn't used for the orchestra to pitch A to. Or if they didn't tune to the piano in place, which he always complained wasn't tuned to pitch anyway. However the person with perfect pitch is extremely rare statisically. The human senses are not that resolute or precise. A device is always more precise in this respect.
However, a device cannot interpret music or determine if it is performed well, nor can it derive pleasure or emotional response from it. But what electronics can do is measure whether another electronic device is doing its function accurately or properly. It can precisely read what the human senses cannot determine. Can your skin and sense of touch give you an accurate voltage reading? No. Can your ears and minds-eye give you and accurate picture or measurement of amplitude response. No. Can you say with all certainly what the phase response is of a certain frequency within a passage of music played through a speaker. No way. The human ear and other senses cannot do that to that level of precision. They are not evolved for that purpose. They can only interpret, not measure with certainly.
The limited abilities of human senses is well studdied, well documented and well understood. It is not a theory. It is fact. Comparatively speaking in terms of specific criteria, the human ear can only resolve to a certain degree. For instance it is well understood what the Hi-Lo frequency range limits are regarding human perception of frequency. Human hearing amplitude response is different depending on sound pressure level (munson curves). And these both vary greatly from person to person. For instance the average amplitude differnetial a human can detect is well known to be between 1 to 2dB and for some people as much as 5dB. Any modern spectrum analyser can resolve to about .1 dB or even lower in some instruments. And this level of precision has existed for some 30 years now. Human hearing cannot, has not and never will be able to resolve at that level of precision. Can a spectrum analyser tell if Itzak is playing? Of course not. That's not its function; not can it, will it nor has it ever been able to.
Interpreting music and measuring things like voltage, phase and amplitude are two entirely different things. You're comparing apples to rocks. They are two completely different unrelated things.
Edits: 11/24/12
Perfect pitch is present in one in ten thousand, more so in Asian populations.
While A=440 is standard, a piano is not tuned to standard pitch machines. As you go up the scale, the pitch rises, as you go lower the pitch goes flatter. The notes increase their deviation as you go depart from the A=440.
That's why Bach is famous, he created the equal tempered scale, or at least popularized it. The human ear is logarithmic not linear. This applies to octaves and the notes between.
Try taking an electronic tuning machine and use it to tune a piano. I guarantee you that it will be the worse sounding piano ever. That's why piano tuning is still very much an art, rather than a science.
As for A=440: That in itself is an artificial contrivance. Over time A could have been much higher as much as 450+. Mozart did not use A=440 as a standard.
Stu
My wife's Steinway B was tuned to A=442. The technician we used to use was the tuner for the Boston Symphony Orchestra, and he tuned to the orchestra's concert pitch.
As you pointed out, pianos aren't tuned with equal octaves, even if each octave is split equally. The linked article explains why. Our tuner explained to me one day what he was doing and why, and that he was making various sonic tradeoffs, including the brilliance of the instrument.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
"Interpreting music and measuring things like voltage are two entirely different things. You're comparing apples to rocks. They are two completely different unrelated things."
Seems to me, if we could ignore your snake oil references for the moment, your OP is guilty of exactly that!
I am the OP. We are talking about using test equipment to get electronics to work properly. Some perople seem to think you do this by ear. You cannot know with any certainty if a loudspeaker is operating as designed unless you measure it with electronics.
People who judge stereo by using ears are missing an important thing. Accuracy. If a violin plays one note, it is recorded, then the playback system (as well as recording system) must pass the information as an electronic signal, not as music. Once this is done, the intergrity of that signal must be maintained through the subsequent stages of electronics. For this to happen the equipment must be tested by measuremnet of electronic signals for accuracy. You cannot do this by ear precisely enough. That is the basis of this discussion. If your manufacturers of this gear didn't have test equipment this stuff would sound like gak!
We are talking about electronics and electronic signals, NOT the interpretation, performance or creation of music. Stereo systems are not musical instruments. They do not create music. They are not used to generate music. They are not used by musicians. They are not the source of the music. They are not inherantly musical. They are electronics, that must perform accurately in the electronic realm and deal with signals, not music. And signal accuracy is quantifiable only through measurement and should not be determined by direct human senses & interpretation. This is what audiophiles, many of them, forget. It's a misinterpretation of realities.
Try this. :-) Wedge the speaker end of your speaker wire in your ear, turn the volume to maximum, and tell me what you hear? In addition to probably going deaf and feeling a strange electric shock, I know you will not hear music. But what you will perceive is the electrons charge flowing through a wire and now into your flesh. (Disclaimer: I'm being dramatic here, do not do this.) Now do this with an electric guitar that isn't plugged in. Just put the headstock on your temple. You will hear music. That's because it's an instruemnt. A stereo is not an instrument, its electronics.
Stereos do not make music. They store and recall electronically a close approximation of a performance of music.
On the contrary the output of a stereo is music and the stereos performance should be first and foremost judged on it's ability to recreate music.As far as your accuracy point goes someone like me must concede the issue however if the stereo is good enough to provide musical enjoyment over a wide diversity of music styles and recording qualities some degree of measurable accuracy will be required - no doubt excess colorations alienate recordings but the colorations accepted will be less than excessive and selected to expand ones musical horizon. This IMO is the purpose of owning a nice stereo - to expand our musical horizons via enjoying all kinds of music. A great stereo is required!
On the other hand, some who listen, can and do make objective listening observations based on experience and training. This methodology bypasses the need to attempt to quantify measureable parameters. So it's true that these kinds of systems may measure less good what's important is that they perform well enough to fool the experienced listener into believing what they are hearing is live. And that's a requirement that cannot be substantiated by any measurement or conglomeration of measurements.
Certainly for most of us who chose to judge a stereos performance by ear it seems outrageous that someone could conclude a stereos performance based on measurements.
Edits: 11/24/12 11/24/12
I think you and I are heading towards some mutual agreement in concept.Understand, my criteria is as the person responsible for creating the recordings being listened to. I was a staff engineer for Sheffield Labs (and many other recrdings over the past 30 years). I have a reference that exceeds that of the casual listener or even hardened expert audiophile. I was there. I placed mics. I built the mic preamps. I heard the actual performance. I know the rooms. In some cases, I even designed the rooms and created the acoustical environment for the recording. I know the actual imaging and placement of the instruments; I put them where they appear to be on the recording. All this on a very intimate and subtle level.
I have heard these recordings of these performances played on some very famous systems (some featured in magazines) and thought the recording sounded competely different than what I know they really sound like. (Of course being very careful not to expose what I was really thinking to the owners of these very costly and lovingly created macinations. It's like calling somebodys kid fugly!) And therein lies the problem of accuracy, for me in particular. The sound system is not making the music, the musicians made the music, I recorded it and turned it into electronic signals and these systems failed (miserably in some cases) to accurately recover the signals and covert them back into sound waves.
Herein lies the problem of perception. I say a sound system doesn't make music, it mearly is a another medium by which it travels. And that music should pass through this medium undisturbed. A sound system should be transparent. What goes in, is what should come out between all stages. Otherwise you are listening to the system itself, not the music. A person with no true reference as to what is going in, has no way to tell what is coming out is the same. But, with measurment one can test the electronics for its ability to pass signals undisturbed. This is not magic, its simple common sense. Recorded music is just signals. If a piece of gear can do its respective job (coverting digital to analog signals, routing the signals, amplifiying the signals, or transducing these electrical signals back to sound waves) without modifying the signals (whether test tones or music; a signal is a signal in electronics), what comes out will be the same as what went in, in every detail as recorded. There is no magic, no human context within this process. However, once the music is liberated from being a signal, and is no longer constrained within electronics, the music is preserved if only in reproduction of sound waves. The enjoyment is maximized and the artists endeavors can be properly interpreted and appreciated fully.
On these systems it was no longer the same music, nor the same performance. Why? Because the system doesn't make music, it coverts electronic signals into sound waves. And in these cases did so in poor fashion technically. Ironically, these systems are considered milestones in audiophile circles. To me, they are poorly over-tuned impressions of people listening to GEAR without a reference, not music. When asked about how they tuned the system I was told, "By ear ... How else does one do it? And what's better than your human hearing for decerning nuance in music". Problem is they are not tuning instruments. They are tuning electronics. They are not listening to musicians play, they are listening to an electronic recording of musicians playing. Different animal. Different reality.
In fact they are listening to the gear and its anomalies, contoured to their opinion of how music should sound, almost in contempt of the musicians and engineers who recorded the performances. The music is secondary. Inaccuracy run amok, to cater to the whims of the gearheads, so-to-speak.
Look ... what people, especially many audiophiles, do not want to beleive is their is no magic, no religion, nothing ethereal about sound systems. All that is needed to be known to reach the goals is well understood. The problem lies in the physics of building this electronics in way where it does its job perfectly. We know where to go, we have full understanding of the physics of sound, human hearing, sound waves and how they work, how to covert signals into sound waves. We know the endgame, the coaches know the plays, we just don't have talented enough players. We just don't have the materials to build "The Stuff". Components like capcaitors are not perfect, resistors and semi-conductors have compromises. Loudspeaker drivers have that nasty reality of the physical world known as mass. The stuff doesn't work perfectly. We have full knowledge, there is just no magic cure for inaccuracies in the stuff! However, when we start messing around with the ethereal, beleiving in magic bullets, and ignoring physics in some cases becuase of the lie of "we can't know all that there is to know" in some arrogant attempt to make things "more musical" we run the risk of changing the recording into something it is not. Something else. Not music, electronic noises and distortions mimicing one persons perception of music. Not what was recorded by the makers of the recording of music for sure. That includes the ludicrous attempts at making bad recordings sound better. If it was engineered badly, you can't replace what isn't there with gear ... or Mrytlewood (hehe).
Having a true musical reference can really suck sometimes! :-)
Edits: 11/24/12 11/24/12 11/24/12 11/24/12 11/24/12
Nice response.I'm not going to continue to defend the objective listeners position because I don't agree with it and ultimately my pov is going to be very similar to yours. All I want to say on that is people can define the job of the stereo to be whatever it is they want it to be. I don't think that more than a few audiophiles are capable of building a true and accurate musical reference using that methodology inspite of what they believe. In fact I think the dissatisfaction with their results leads to continued purchasing but that's just what I've observed.
Where you lose me is with a comment like "That includes the ludicrous attempts at making bad recordings sound better. If it was engineered badly, you can't replace what isn't there with gear ... or Mrytlewood (hehe)."
You sound so much like a recording engineer! What's a bad recording? Heck a bad recording sounds like a bad recording but in my book that doesn't mean it sounds bad. And a good recording sounds like a good recording but it doesn't mean it sounds good. Of course our stereos should be good enough to differentiate recording quality but it's the quality of the inaccuracy within the system that threatens to limit our ability to enjoy a diversity of recordings or may enable us to enjoy a wider diversity.
I'm not saying compression, clipping and eq sounds good but given reasonable volume levels lots and lots of popular music can deliver great listening experiences for those who are interested.
Like I said in my response to your Original Post, the most measureably accurate stereo may be the best but given the fuzzy specifications for the universe of recorded works it seems highly unlikely it would be chosen by listening. Of course one could select recordings that tend to substantiate any desired conclusion.
I agree there is no magic - there's only selecting equipment that works well together whose shared strengths and compromises best meet the owners expectations.
Edits: 11/25/12 11/25/12
"
"Is global warming real? Hehe."Those of liberal political persuasion think it is........... I personally haven't seen any objective evidence."
You personally haven't seen any objective evidence? The Fing polar ice caps are melting, the temperatue and level of the ocean is rising, and climate is changing and you claim you haven't seen any objective evidence? There is no question global warming is real and it's got nothing to do with one's political persuation, I suppose some party of idiots might deny the the clear and unquestionable evidence.
And for whatever it's worth I can't even dismiss creationism as who knows what state the earth was created in - far as I know the world could have been formed 200 BC with all history intact. But global warming? Thats a certainty....
What's in question is how much mankind is accelerating this warming and climate change if at all.
Edits: 11/23/12 11/23/12
I am sure there is analysis that could be performed to determine with reasonable accuracy between the two performers.
Did I read this right - over 28,000 posts?!?!?!?! Your reply started off well, but then it got bogged down in semantics.
28,000 + posts? Mercy!
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