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Post by moko on Feb 18, 2015 11:34:11 GMT -5
like i said before what sound is perceived by our ears is subjective. describing sound would be difficult in the objective way. you'll get better luck by googling it. If you can't define "transparency" then how can you be making statements in this thread about it? Earlier, Keith said it depends on what you mean by transparency. He felt by that it was meant "accuracy." I think that is a reasonable assumption. But how do you really know how accurate something is? If you are talking about accuracy as in your system sounding identical to the original performance, there are way too many variables along the way that will cause what you ultimately hear in your room to vary from the original. The way it was recorded, miked, equalized, your room acoustics, etc. - besides no one really knows what the original performance really sounded like. Even if you were there it depends on where you were seated and what you heard is not what the mics picked up. All along the chain, things can be measured. You are right, what is perceived by our ears is subjective but I don't think that strengthens your argument any. That has nothing to do with claiming that there are differences in sound that cannot be measured. lol, you guys love to twist words. please read the first post of this thread about a bit of description of what the transparency is. i wonder why you bother with recording techniques when all you have to do is comparing what comes out from speakers with the same materials ? like i said before what sound is perceived by our ears is subjective. describing sound would be difficult in the objective way. you'll get better luck by googling it. Does this transparency have a different sound to you? I'm guessing it does. Is that difference not manifested in a difference in the speaker cone movement. Or is the sound somehow different with the exact same cone movements? geebo, that's what exatly what i'm asking here : can you put a microphone in front of speaker and measure transparency ?
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geebo
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Post by geebo on Feb 18, 2015 11:44:26 GMT -5
If you can't define "transparency" then how can you be making statements in this thread about it? Earlier, Keith said it depends on what you mean by transparency. He felt by that it was meant "accuracy." I think that is a reasonable assumption. But how do you really know how accurate something is? If you are talking about accuracy as in your system sounding identical to the original performance, there are way too many variables along the way that will cause what you ultimately hear in your room to vary from the original. The way it was recorded, miked, equalized, your room acoustics, etc. - besides no one really knows what the original performance really sounded like. Even if you were there it depends on where you were seated and what you heard is not what the mics picked up. All along the chain, things can be measured. You are right, what is perceived by our ears is subjective but I don't think that strengthens your argument any. That has nothing to do with claiming that there are differences in sound that cannot be measured. Does this transparency have a different sound to you? I'm guessing it does. Is that difference not manifested in a difference in the speaker cone movement. Or is the sound somehow different with the exact same cone movements? lol, you guys love to twist words. why you bother with recording techniques when all you have to do is comparing what comes out from speakers with the same materials ? geebo, that's what exatly what i'm asking here : can you put a microphone in front of speaker and measure transparency ? Can you measure airy, or buttery or smoother as it is used to describe sound? Transparency is just another one of those subjective terms that mean different things to different people and has no real meaning. Transparency is a visual trait that can indeed be measured. It's not an audio trait any more than airy is. If the speakers are doing something different and nothing else changes then the difference can be seen or measured because the electical signal going to the speakers is different. Now how you equate the measured difference with some subjective term is where the problem arises.
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KeithL
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Post by KeithL on Feb 18, 2015 12:05:18 GMT -5
To reply directly to that statement "what i'm saying is that NOT ALL differences can be measured by ANY type of measurements method"..... What I'm saying is that you are in fact mistaken. The sound reaching each of your ears at any given instant is in fact two dimensional. However, since the instrument producing the sound does so in three dimensions, and sound travels in three dimensions, and your head and the room you're sitting in also exist in three dimensions, that two dimensional sound wave arriving at your eardrum is affected by the shape of your head and the shape of the room. If a guitar, a piano, and a violin all produced a pure "C" note, then they would indeed sound identical. However, in fact, each produces a primary frequency, and a whole complex collection of harmonics, each with a different phase relationship to the primary frequency, and each leaving the instrument in different directions. It is the different levels of the different harmonics, and possibly even the phase relationship between them, that makes a violin sound different from a piano or a guitar. (If you look at the notes produced by all three on an oscilloscope, it's pretty easy to see the differences, and we can measure those differences in precise detail using other equipment.) In fact, there is no single thing that your human hearing can hear that we cannot measure more accurately using some piece of test equipment. (Human hearing has a wider range of capabilities overall than any single piece of test equipment, but the capabilities of the overall selection of test equipment available far exceeds the range of human hearing in every way.) Where the human brain excels at is multitasking - which, in the case of music, means that it can detect and analyze a wide variety of input stimuli at the same time.... and this is where things get interesting. If you were to sit in a "dentist's chair", with your head clamped in place, and listen to a violin, I could then record that violin and play it back (with the proper equipment), and you would be totally unable to tell the difference (because we are quite capable of making a reproduction of the changes in pressure that are reaching your ear that is precise enough that you wouldn't be able to tell). However, if you were to then move your head, the difference would become obvious - because your brain would "know" how the sound "should" seem to shift when you move your head, and that aspect of the situation would NOT be correctly reproduced. I can pretty easily MEASURE anything your human ears can hear, but what I can't do is to accurately predict exactly how your human BRAIN will INTERPRET what it hears. (So, for example, I can measure that the second harmonic from that violin will arrive 126 microseconds later in time than the primary frequency in your left ear, and only 113 microseconds later in your right ear, and I can even predict approximately where your brain will "visualize" that violin is sitting based on that difference, but how your brain will interpret how high that violin is, based on the arrival times of a few dozen more reflections, is a much more complicated calculation, and we're not quite sure of all the details on that one.) However, the electrical distortions caused by a "bad" capacitor are indeed two dimensional - and can be "described" by an exact representation of voltage over time. There's nothing intangible or unmeasurable about it; at certain times the voltages will be incorrect - as compared to what it should be. And you could quite easily measure, or even record, those differences. The only "question" about differences in capacitors is how audible those differences are, and whether it justifies the extra cost and aggravation of using "better" capacitors. (You could also leave out those coupling capacitors entirely; if you do that you won't have to worry about which one sounds better. However, since part of what those capacitors do is to block DC at the input, without them, if your preamp malfunctions and puts out a bit of DC leakage, you are virtually assured that your amplifier will incinerate your speakers.) The reality is much more dreary and mundane than you seem to imagine. The reason why most amplifier specifications probably wouldn't show the differences in those capacitors is quite simply that, of the many things we could be measuring, most specifications only quote a very few "common" measurements - which, by and large, do tend to be good indicators of how an amplifier will sound. If you were to try and see the differences between those capacitors on an oscilloscope, it's quite possible you couldn't see them (because an oscilloscope only allows you to see differences greater than 5% or so). However, there are other ways of making measurements that could easily tell you what those differences are in precise detail, and, if they are significant enough to be audible, those audible differences could also be easily recorded and played back. (There is no "question" that different capacitors produce different amounts and types of distortion, and there's also no problem with measuring and comparing the performance of each - the only "question" is whether those differences are audible in a given circuit and, if they are, whether they justify the extra cost and space requirements of using "the better one".) If you're curious, here are a pair of articles describing how to measure the audio performance of capacitors (these articles were written in 1980 - although you will find that there are several new types of capacitors now available, and "high-performance electrolytics" perform a lot better than the electrolytic caps of 35 years ago, it's pretty obvious that the ability to measure the differences between capacitors is hardly new). This is the actual science of why different capacitors sound different. waltjung.org/PDFs/Picking_Capacitors_1.pdfwaltjung.org/PDFs/Picking_Capacitors_2.pdfIncidentally, I would agree with you about the measurements being a source of bias, but only if the initial "listening tests" are conducted as a real double-blind test (to eliminate their being an even worse source of bias). Also, many people with engineering backgrounds consider "the numbers" to have a sort of "aesthetic significance". If I were to audition two amplifiers, and find that I liked the way they both sounded, but later discover that one had much higher THD, I might decide against that amplifier because, even though it sounded fine, the THD numbers indicated to me that it was poorly designed - and so I might choose against it on "aesthetic grounds". I would simply prefer to own something that sounded good because it was well designed rather than something that sounded good in spite of the fact that it was badly designed. (It's sort of like the difference between buying a good painting by a good artist, and buying a good painting by a bad artist, knowing it's the only decent thing he's ever done.) But are you saying the differences cannot be measured or cannot be measured with typical manufacturers measurements? what i'm saying is that NOT ALL differences can be measured by ANY type of measurements method. and also i'm saying that sound is a 3 dimensional thing : frequency, amplitude and time. all of these years people only looking at THD graphs and thinking that as long as these graphs look good then it must be sound good. it's the same thing as saying that the sound is 2 dimensional thing. we'll if the sound only has 2 dimension (frequency and amplitude), then guitar, piano and violin will sound the same when playing C note don't be mistaken, i also like looking at measurements. but i never put too much emphasis on measurements because it is a source of bias. if you look at gene and hugo at audioholics.com, when reviewing some equipments they will listen to it first, then measure it. and i think that is the appropriate way because if they do it the other way around, then they will be heavily influenced by bias.
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Post by KeithL on Feb 18, 2015 12:06:14 GMT -5
Yes.... The more expensive part always sounds better (as long as you make sure to display the price tag in a prominent location) well, isn't that just a one man's opinion ? enough with theory, let's put it into practice : even a man with decent electrical knowledge can make that xpa-200 (or any amp) sounds less transparent (more muddy) in one channel only but the measurements will look the same on both channel. how ? by changing the DC blocking capacitors in the audio signal path with super duper CHEAP, low quality, nasty electrolytic capacitors of the SAME value.this way you'll get same frequency response, same THD numbers, same power but it will sound DIFFERENT between left and right channel. Ahh the more expensive part always sounds better. Even there (more expensive means better) the brain fools you.
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Post by monkumonku on Feb 18, 2015 12:08:35 GMT -5
I must confess that after going back and reading through this thread, Moko, I am not really sure exactly what your viewpoint is. I guess I am unable to measure it. The most rewarding thing I found in this thread was the picture of Selma Hayek.
My two cents, we all hear what we hear. If you like the way your system sounds, then that's great, and it shouldn't matter what the measurements say or how much the components cost or anything else, as long as you like what you hear. If you think it is transparent and one of your goals is to achieve transparency and you feel you've achieved it based on however you define it, then that's great, too. But I say all those things that make a particular configuration more pleasing to you than another one can be measured in some way. There's no such thing as differences in sound that cannot possibly be measured.
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Post by pedrocols on Feb 18, 2015 12:26:26 GMT -5
I must admit my ears are terrible at measuring anything.
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Post by KeithL on Feb 18, 2015 12:28:50 GMT -5
I'm going to ask a really obnoxious question here.... About perspective.... If someone is going to claim that Product A is worth 5x as much as Product B, then shouldn't they be able to show an obvious, significant, and repeatable difference? And isn't this especially true if the products in question are expensive to begin with. If I'm choosing between two $29.95 interconnect cables, I don't see a major obligation on the part of either manufacturer to "prove" that theirs is better. Likewise, if I'm choosing between a $2.99 cable and a $14.99 cable. However, if we're talking about the choice between a $29.95 interconnect and a $500 interconnect, I think the bar really should be a lot higher. (I could have bought better speakers, or a really nice DAC, for the price of that cable.) And, to put it bluntly, for that much of a difference, I'd better be able to hear a huge difference, every time, in dark or in light, and after a six pack..... If I suddenly can't hear the difference with my eyes closed, or when someone else flips the switch, then "Houston, we seem to have a problem". If you're asking me to even consider paying FIFTEEN TIMES AS MUCH for your product, then the difference hadn't ought to be "subtle". And, to be brutally honest, if I'm the only one in the room who can hear it, then I AM going to wonder if it's real (as in "$470 real"). Yes, it's true that a lot of people really can't tell the difference between Coke and Pepsi - but nobody's trying to get you to pay $50 a glass for either one. This goes back to that quote about "Extraordinary claims require extraordinary proof". In most of these situations, we actually have TWO extraordinary claims: 1) That, in spite of the lack of legitimate science to back up the claim, that one product is actually better than another. 2) That, even assuming we accept the first claim, that the difference is WORTH THE EXTRA COST. Here's my question, once and for all, to everyone who doesn't like double blind tests: Do you have a better way? Do you have a better way to minimize the opportunity for contamination by bias? Do you have a better way to tell the actual objective reality of the situation? I also wanted to address the final comment about "proving" that a difference doesn't exist. The fact that 1000 people are unable to identify a difference absolutely DOES NOT prove that no difference exists, nor that the one guy who claims that he does hear a difference is wrong. HOWEVER, if 1000 people claim to hear a difference, then further tests show that the difference mysteriously vanishes when they're blindfolded, then that DOES strongly suggest that the original claim of a difference was untrue, AND that those original 1000 respondents were either lying or being unconsciously biased somehow. (And, if that one guy mysteriously loses his ability to tell the difference when he listens with his eyes closed, then there's no reason we should believe his claim that he heard a difference either.) Hey if I can't pick it out in a double blind test but you can more power to you. The thing is, when a real double blind test is done, no one seems to be able to either. If you are the exception, there are people giving away real money for these tests. Just remember a 50% right answer doesn't prove a difference. Also I never said that YOU are not hearing a difference I just pointed out some possible scientific explanations as to why. But voodoo audio science isn't it. is that the double blind test that involves human memory ? i would not call that accurate. i think it has 1 big flaw : human memory is short. although KeithL a bit disagree with me and said it has MANY flaws i would not call making a theory and then claiming ANYONE can not hearing a difference is scientific. in the scientific way ALWAYS involves a practice in which you did not do it like pallpoul did.
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Post by KeithL on Feb 18, 2015 12:45:19 GMT -5
The "meta definition" is simple - transparency means "not being visible". When you translate this to audio, this means "not affecting the original in any way".... unfortunately, while the concept is simple, the reality (and measuring it) sometimes is not. (If you're testing a preamp, you divide the output down to the same level as the input and do an A/B test; if you can tell ANY difference, even when the levels are perfectly matched, then it ISN'T transparent. Unfortunately, with things like speakers, none of which are truly transparent, it always ends up being a comparison of which errors in perfect transparency are most annoying to which of us. (Remember the old "Is it real or is it Memorex?" commercial?)
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geebo
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Post by geebo on Feb 18, 2015 12:54:14 GMT -5
The "meta definition" is simple - transparency means "not being visible". When you translate this to audio, this means "not affecting the original in any way".... unfortunately, while the concept is simple, the reality (and measuring it) sometimes is not. (If you're testing a preamp, you divide the output down to the same level as the input and do an A/B test; if you can tell ANY difference, even when the levels are perfectly matched, then it ISN'T transparent. Unfortunately, with things like speakers, none of which are truly transparent, it always ends up being a comparison of which errors in perfect transparency are most annoying to which of us. (Remember the old "Is it real or is it Memorex?" commercial?) I guess lack of transparency would be distortion then.
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Post by jmilton on Feb 18, 2015 13:15:29 GMT -5
I must admit my ears are terrible at measuring anything. My ears measure differently than yours. However, finding a good pair of headphones can be challenging.
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bootman
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Post by bootman on Feb 18, 2015 13:48:55 GMT -5
I must admit my ears are terrible at measuring anything. My ears measure differently than yours. However, finding a good pair of headphones can be challenging. Everytime I see that pic i'm reminded of this. ...and now this thread has officially gone off the rails.
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Post by bub on Feb 18, 2015 14:36:58 GMT -5
Has anyone seen Salma?
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Post by pedrocols on Feb 18, 2015 19:58:48 GMT -5
Let me go to my room and check. I'll be back...
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Post by ocezam on Feb 18, 2015 23:18:28 GMT -5
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Post by leonski on Feb 19, 2015 4:39:51 GMT -5
At least as far as electronics goes, one thing I'd expect for more money, even if 2 amps are built from the SAME schematic would be a higher MTBF for the more expensive amp. For example: Bryston Amps which ARE Uber Expensive also have a 20 year warranty. Believe me, you ARE paying for that. But before Bryston ships an amp, it goes thru an extensive factory burn-in procedure designed to weed out defective amps. Be that defective for parts or construction.
Cables are a cool example of cost / benefit / perception.
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Post by bub on Feb 19, 2015 7:05:06 GMT -5
She always puts a smile on my face....Thanks
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Post by moko on Feb 19, 2015 15:03:16 GMT -5
geebo : yep, transparency is a subjective terms just like how our ears perceived sound. it's just a tool to describe sound. without those subjective terms, how can you describe sound ? would you say like this to describe sound : "wow ! that sounds accurate because it has 0.001 % distortion !" now, you are mistaken by saying it has no real meaning. contrary, it has BIG impact on purchasing decision by anyone who wants to upgrade their system. if people feel that their system is lacking one of those subjective terms, they will look for REVIEWS instead of distortion numbers because those numbers are more alike the same. maybe you can measure transparency in visual world, but until now i can't see they able to measure it in audio world. KeithL : "what i'm saying is that NOT ALL differences can be measured by ANY type of measurements method" is related to transparency which until this day you still cannot measure it. about sound is 3 dimensional is a diferrent topic. here's my view : you claimed that the differences in those instruments when playing C note is only in the harmonics structure. with the 2nd harmonics usually more dominant, let's say guitar has 2nd harmonic at -60 db down from primary note, violin has 2nd harmonics at -65 db, and piano -70 db. the question now arise : can you hear the differences of harmonics down at that level ? the biggest flaw in that claim is that we still don't know about the shape of sinewaves of each instrument. what if they are not sinewaves ? what if it's a synthetizer which can produce squarewaves ? to know exactly the shape of those waves we need oscilloscope to measure it in time domain. so there you go : frequency, amplitude and time. about caps : from that pdf articles it seems electrolyctis caps are the worst choice. although now electrolyctis are better, but i bet other types of capacitor also improves and still better than today's electrolytic type. another question has arise : why emotiva still using electrolyctic caps as dc-blocking capacitor in their less expensive products ? to fit into certain price point ? about double blind test : the only accurate way is by testing in blind way, source set to mono, left channel using different test subject (equipments/cables) compared to right channel and volume is matching and constant. this way you'll eliminate bias and human memory involment.
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geebo
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Post by geebo on Feb 19, 2015 16:09:53 GMT -5
geebo : yep, transparency is a subjective terms just like how our ears perceived sound. it's just a tool to describe sound. without those subjective terms, how can you describe sound ? would you say like this to describe sound : "wow ! that sounds accurate because it has 0.001 % distortion !" now, you are mistaken by saying it has no real meaning. contrary, it has BIG impact on purchasing decision by anyone who wants to upgrade their system. if people feel that their system is lacking one of those subjective terms, they will look for REVIEWS instead of distortion numbers because those numbers are more alike the same. maybe you can measure transparency in visual world, but until now i can't see they able to measure it in audio world. KeithL : "what i'm saying is that NOT ALL differences can be measured by ANY type of measurements method" is related to transparency which until this day you still cannot measure it. about sound is 3 dimensional is a diferrent topic. here's my view : you claimed that the differences in those instruments when playing C note is only in the harmonics structure. with the 2nd harmonics usually more dominant, let's say guitar has 2nd harmonic at -60 db down from primary note, violin has 2nd harmonics at -65 db, and piano -70 db. the question now arise : can you hear the differences of harmonics down at that level ? the biggest flaw in that claim is that we still don't know about the shape of sinewaves of each instrument. what if they are not sinewaves ? what if it's a synthetizer which can produce squarewaves ? to know exactly the shape of those waves we need oscilloscope to measure it in time domain. so there you go : frequency, amplitude and time. about caps : from that pdf articles it seems electrolyctis caps are the worst choice. although now electrolyctis are better, but i bet other types of capacitor also improves and still better than today's electrolytic type. another question has arise : why emotiva still using electrolyctic caps as dc-blocking capacitor in their less expensive products ? to fit into certain price point ? about double blind test : the only accurate way is by testing in blind way, source set to mono, left channel using different test subject (equipments/cables) compared to right channel and volume is matching and constant. this way you'll eliminate bias and human memory involment. Transparency is a visual term. It has no real objective meaning in audio. You might as well say it sounds less gelatinous and let's see you measure gelatinous in audio. Or chocolaty. Or gooey. With the myriad items that can be and are measured in audio how do you know they don't reveal what you describe as transparency. If transparency means anything in audio, it would be a lack of distortion which can easily be measured. If the sound is different, the speakers are doing something different and if the speakers are doing something different the the signal feeding them is different and that difference can be measured. No, there is no transparency measurement or buttery measurement but there are measurements that reveal what you hear. Give what you hear any descriptive term you like. You just don't know what measurement is responsible for what you describe.
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bootman
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Post by bootman on Feb 19, 2015 16:57:50 GMT -5
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Post by leonski on Feb 19, 2015 18:11:00 GMT -5
These guys in the video are MISSING THE BOAT. They talk a LOT about impedance as a drive behind amp problems. But really, you CAN have 2 amps which BOTH measure the same into a resistor at 4 AND 8 ohms, and STILL sound different. The problem is with REAL speaker loads which are reactive. IOW, they look like a CAPACITOR or INDUCTOR to the amp in question. 2 amps which measure the same or within <1db into a resistor will seldom measure the same into a REAL speaker load. It is begging the question to just keep talking about impedance, sensitivity and listening level with NO mention at all of reactance. Standard loads DO exist which are 'simulated' speakers and have plenty of reactance to test most consumer amps. For the Hard Core, I'd recommend the Power Cube measurement system. Here is link: www.ap.com/kb/show/206Other info on this sytem exists and even other efforts to come up with a 'standard' load with real reactance.
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