Not sure why you're putting words in my mouth. No, I’m not saying that. Wow.
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Electrons carry charge, whereas the music signal is an electromagnetic EM wave so it (the signal) must travel in a conductor at near lightspeed. In order to travel at that speed the wave must be, physically, photons, not electrons. The electrons in the conductor only travel what a meter an hour or something. If the audio signal wasn't light speed you would hear a pretty big delay for normal phone conversations, no?Wow. Just wow. So are you saying that there is no current flow in a vacuum tube or a transistor? That its all photons? or does the the photon flow turn into electron flow once it hits the tube? Wow. |
Roger, "I believe you can have both a neutral system and a natural system. After all - if your understanding of "neutral" means no top end or bottom end exaggerations or no coloration's etc., wouldn't the default term be "natural" as well - meaning that a system that can deliver a flawless performance in your listening room would have to be considered natural?" Generally speaking, I certainly believe that if you do have a neutral sound then the overall result will indeed be more natural overall, no question...and as far as that goes, I would add that there would also be more realism as well. At least, that's what I'd say I am experiencing here. But, the idea of neutrality as a separate issue was raised that way in the OP and that was the way I was responding to it...but, yes, I regard it as simply an integral part of the whole. But, if you ask me, I would think that trying to pursue realism and naturalism without neutrality might make for a little tougher sledding in the long run, but to each his own, I suppose. "This is an interesting observation which can mean one of two things. 1. You have very good gear with not too much of a problem with external interference. 2. You have arrived at a combination of gear that has masked the benefits or the "sounds" of either configuration." Yes, IME I find it's actually a rather striking observation (which is why I made the comment, really), but that has been one of the differences made by Alan Maher here. In truth, I would say I have moderate gear and a greatly reduced level of external interference...far below what is normally encountered. Again that's from the AMD here. "Except now it is worse because if they upgrade one component that gives them truly better detail, it further exposes a harshness in some component up stream and they either have to get another replacement for it or put the first one back in so it is tolerable." That is what the AMD here is really all about. It has eliminated that result for me. Instead, all I've had to consider all the technical aspects of system synergy. Reducing the noise in the system's environment wholesale has allowed me to consider a far wider range of equipment without ever running into the "harshness" conundrum. It even allowed me to use less expensive gear and get stellar results. "When someone gets the bug be can't afford much, the old guys tell the newbees how to get the best sound for the buck. You simply get a "bright" sounding preamp to drive a "good" power amp with poor top end that emphasizes the mids and bottom end. This uses one component as pre-emphasis and a second for de-emphasis. You end up with the perfect mix of zig and zag and you save a lot of money. Yes? Well, it might be a good place to start but it will be quickly disappointing. It is hard to fool your ears with anything that contains distortion - even if it is the "good" kind." Agreed, this is always worth avoiding...although to be fair, the old guys, whenever they may be handing out such advice, are usually up against the most severe budget restraints of newbees when they do so, but personally, I'm with you. Regards John |
Ivan, switching out between single-ended and balanced has no longer made an audible difference, under my roof This is an interesting observation which can mean one of two things. 1. You have very good gear with not too much of a problem with external interference. 2. You have arrived at a combination of gear that has masked the benefits or the "sounds" of either configuration. I believe you can have both a neutral system and a natural system. After all - if your understanding of "neutral" means no top end or bottom end exaggerations or no coloration's etc., wouldn't the default term be "natural" as well - meaning that a system that can deliver a flawless performance in your listening room would have to be considered natural? If two audiophiles went to a live concert - how would they describe the performance to each other? Would they use terms like "sweet top end" or "detailed mids" or "smooth" or "rich"? No. They would say what non-audiophiles in the audience would say.. "It was awesome" "It was overwhelming" "It was thoroughly enjoyable music" This is how audiophiles want their home systems to sound. Unfortunately they have to go through months and years of swapping this for that until they "bump into" the best compromise. Except now it is worse because if they upgrade one component that gives them truly better detail, it further exposes a harshness in some component up stream and they either have to get another replacement for it or put the first one back in so it is tolerable. On most of these threads you see a pattern of some wisdom. When someone gets the bug be can't afford much, the old guys tell the newbees how to get the best sound for the buck. You simply get a "bright" sounding preamp to drive a "good" power amp with poor top end that emphasizes the mids and bottom end. This uses one component as pre-emphasis and a second for de-emphasis. You end up with the perfect mix of zig and zag and you save a lot of money. Yes? Well, it might be a good place to start but it will be quickly disappointing. It is hard to fool your ears with anything that contains distortion - even if it is the "good" kind. Roger |
Atmosphere wrote, https://en.wikipedia.org/wiki/Photon -From the page: A photon is massless,[Note 3] has no electric charge,[12] and is stable. I never said a photon did have mass, or that it had an electrical charge or wasn’t stable. But electrons are carriers of *charge* not the audio signal. The electromagnetic wave that is the actual signal is made of photons. Just like (visible) light but with a different wavelength. Gamma rays, x-rays same thing - Photons with a different wavelength than visible light. The electromagnetic spectrum is extremely wide and includes obviously visible light which is obviously just a very small part of the whole thing. Electrons in the conductor are almost at a standstill, but the music signal is moving at near light speed (since it’s made of photons). That’s what I mean by carrier. The radio wave (RF) does not need a medium in which to propagate, obviously, since it will propagate in a vacuum. Just like a radio transmission to a satellite is comprised of photons. Or an ELF transmission. Atmosphere also wrote, "However it also states that it is a form of EM radiation." Electromagnetic radiation. Now we’re getting somewhere! I am agreeing with that statement. That's what I’ve been saying, that light and radio waves are electromagnetic waves, radiated. The units of measurement for satellite communication transmission is surprise, surprise, EIRP, Effective Isotropic Radiated Power. atmosphere also wrote, "However the signal in a cable is not carried by photons. A better carrier would be the electron, although stated in those terms might be considered a gross oversimplification." Electrons carry charge, whereas the music signal is an electromagnetic EM wave so it (the signal) must travel in a conductor at near lightspeed. In order to travel at that speed the wave must be, physically, photons, not electrons. The electrons in the conductor only travel what a meter an hour or something. If the audio signal wasn't light speed you would hear a pretty big delay for normal phone conversations, no? |
Understood. Last I checked, I believe my system was full differentially balanced, but since some of it is modified I should 'triple check' that, to be sure. But, to make clear for anyone else, I've certainly found balanced lines to make an audible difference in my systems (the degree of which depending on the gear) prior to using AMD. It's just that after doing so, switching out between single-ended and balanced has no longer made an audible difference, under my roof. |
https://en.wikipedia.org/wiki/Photon -From the page: A photon is massless,[Note 3] has no electric charge,[12] and is stable. However it also states that it is a form of EM radiation. However the signal in a cable is not carried by photons. A better carrier would be the electron, although stated in those terms might be considered a gross oversimplification. Ivan, if you had read the thread through (and I don't blame you for not doing so) you would see that I brought up the balanced line thing specifically with respect to the fact that if properly executed (and quite often in high end audio, the balanced line standard is pretty well ignored) then the cables at least will be immune to EMI (stray magnetic field) problems. If you do not hear that in your system then its likely that it is not supporting the balanced standard. |
Atmasphere, the real ’good and valid point’ I felt Geoff to be making there (and I didn’t fully make this clear above) is simply that magnetic fields do have an adverse impact on sound. Who is right or not on the theoretical details I’m not really qualified to answer. " This was around the issue of balanced line connections, which can be used to eliminate problems of cable construction and colorations as well as the effects of magnetic fields impinging the cable. BTW, this is not to say that EMI/RFI isn’t a problem; Geoff was right about that); what I am saying is the if you run balanced lines and the equipment supports the balanced line standard then the cables will have almost no effect on the sound and it will get around the problem of EMI impinging the cable." This is technically true. However it is Wholly insufficient to fight either magnetics or EMI/RFI in the **system** - that is to say with its sonic performance overall. This is because they both have Sooo many other points of entry into the system and just protecting the IC’s alone can never, and will never, cut it. My system uses balanced lines from source to amps. But, if that were anywhere near sufficient by itself, then the $10k’s worth of Alan Maher Designs gear I’ve bought over the last few years that is designed specifically to deal with both magnetics And EMI/RFI should have made no impact on the sound and that is plainly not the case at all. It makes a "night and day" difference...and yes, as in a ’whole new system’ level of difference. What I’m saying is that balanced lines, in the grand scheme, make no appreciable difference...**once you’ve caught on to just how bad the overall picture of magnetics/EM/RF vs system performance actually is**, that is. |
Hi, Atmosphere, sorry to abuse you of some of your beliefs but photons are the "carriers of the electromagnetic waves, which is what Radio Frequencies are. That’s why, as I already said at least three times, that radio waves travel at light speed, because it’s comprised of photons. Can you think of anything other than photons that travels at light speed? Actually, now that you bring it up, he music signal in cables and wires is also an electromagnetic wave and is also composed of, uh, photons. What about x-rays? Yup, photons. The ELF transmission at 75 Hz? Photons. |
Geoff, its really obvious that you did not read any of the links to basic information about the nature of EMI and RFI. Don't worry about me, you still have to get 'yet on the same page' with some of those basic rules to which those links referred. FWIW photons are a phenom normally associated with light, not RFI or EMI... Our gear does not have problems with stray magnetic fields on account of the fact that its fully differential and thus a great deal of shielding is not required. Differential circuits, if laid out correctly, can reject noise from magnetic fields (EMI) just as they can Common Mode noise and for the same reason. |
That’s so funny. We are not yet on the same page. No problem, I’m very patient. You on one hand are talking about RFI and EMI while I’m talking about magnetic fields. Think back, way back, to high school and the right hand rule. The right hand rule for determining the direction of the induced magnetic field produced by current traveling through a conductor. As I said previously RFI/EMI is light speed due to the photons involved whilst the other - magnetic field - is stationary. Apples and watermelons, my friend. |
(I happen to think Geoff was in the middle of making a very good and valid point about magnetic fields here originally before he was so shrewdly interrupted ;-)He got interrupted because he didn't understand how magnetic fields worked. This was around the issue of balanced line connections, which can be used to eliminate problems of cable construction and colorations as well as the effects of magnetic fields impinging the cable. BTW, this is not to say that EMI/RFI isn't a problem; Geoff was right about that); what I am saying is the if you run balanced lines and the equipment supports the balanced line standard then the cables will have almost no effect on the sound and it will get around the problem of EMI impinging the cable. |
Neutral IS attainable...very much so; as a valid audio concept it is alive and well, even if only in a purely subjective sense. But, brightness, darkness or bass-heavy etc, are nothing more than frequency response issues and can be fully corrected as such. What cannot be corrected in that way are the effects of colorations. That is a different problem with a different solution. I’m not talking about just speaker boxes, although that is certainly part of it. What I’m talking about here are the colorations in the components, passive crossovers and the wiring - ALL of the wiring...power cords, IC’s, speaker, all the in-wall wiring, breaker box wiring - everything. Yes, it is about EMI/RFI and yes, it is about magnetic fields. (I happen to think Geoff was in the middle of making a very good and valid point about magnetic fields here originally before he was so shrewdly interrupted ;-) But, be that as it may, there’s still such a thing as non-neutral gear, pro or audiophile. We’re all probably aware of the nature of, say, the amp market at around, say, $3k or less. ’Rogue’ amp designers trying to make a name for themselves by giving us "more" of some particular favored attribute when we really know that it really can’t happen that way without giving up some other still-desirable attribute in the design process. We know this is true because if they were able to give us more of the good stuff without ever sacrificing anything elsewhere, then everybody would be making amps that way...there would be only one way to go to get the best sound and clearly that’s not the case, is it? There is no free lunch. And then there are, just for example, all those low cost tube amps that are known (and even sought) for their colorations (yielding some ’tonal color’ to a degree and "sweetness")...whether those colorations predominantly belong to the tubes they are using or to their amp design. I don’t really want to take anything away from those folks who prefer going this route, it’s all good and perfectly valid...it’s just not my particular cuppa, but I respect it 100% but, that’s because I know there are so many more buying factors that go into those choices than what I can include here. My prior amps were the little (but mighty) Monarchy SM-70 Pros (single-ended transistor design). Long on timbre, but short on good string sounds, but overall somewhat colored through the lower mids and to lesser extent up into the midrange. It took a long time for me to fully figure out why I could never get EQ to sound right, no matter how much I experimented, measured or listened. Sometimes it sounded FAR better than I would’ve thought it had a right to - and then suddenly it would sound ’off’ or unnatural on the next disc - or even on the next track. No amount of Alan Maher Designs electrical noise reduction gear could neutralize that. When I ’upgraded’ to the less expensive and pro-sound Crowns I’m using now, Bam - that problem disappeared entirely. EQ now is set it and forget it...no measuring needed. I suspect, though, that for some audiophiles, there may be perhaps too much of this kind of gear available to sift through and because most audiophiles don’t start out with the experience level to avoid buying this kind of gear initially, manufacturers may interpret this as ’demand’ and may respond by making more. But, there may be a certain frustration level out there by those who are not finding the neutral kind of gear they’re looking for, so they may end up feeling they are forced to go the "natural" sound route, instead. Not necessary, maybe, but IMO understandable possibly, given the lay of the land. As for solving colorations (the electrical ones, not physical), I was able to solve that with AMD gear...but, my components had to be inherently neutral enough as well. I define ’neutral’ then as having no colorations, a sound that is equally adept at reproducing "lush", "sweet", "brash" and "shrill". (Also can be used to describe a sound stage that’s neither too far to the front or to far to the rear). Congrats to Peyton Manning! |
Dracule1, I too see no use for the concept of "neutral." I think realism is the goal I seek. One has to know what instruments sound like and hear the human presence around their playing or singing. But recently, I have heard realism at the fringes of the orchestra that are new. The illusion of a three or four person group seems easy but that of a symphonic orchestra or big band is not. I heard it somewhat in the Zandon suite at CES but much more with the new H-Cat X-10 MkIII amp. I no longer will be without this total realism. |
Neutral is too ill-defined as it applies to audio but it seems to be used frequently and many are not sure what it means. If I was interested in purchasing a particular piece of gear I might for a very brief moment want it to sound neutral, forgetting that the end result of any system is based on the combination of several other components. Someone made that word up, so get rid of it. |
I'm only speaking for myself of course but IMO audiophiles tend to over analyze this kind of stuff too much. It's only natural considering the money involved. I've given up the need to over analyze frequencies or any other such stuff to come to a conclusion about my gear. The only thing that maters is what sounds neutral to me. In the end It may not sound neutral to anyone else. In the search for "neutrality" you can go and blame the electronics, the electricity from the walls, the rotation of the earth for that matter. Your chasing a perfect circle. Meaning it's a concept that cannot truly be achieved. So the only person you have to convince is yourself. None of it amounts to anything unless you like it yourself. All this talk about what is and what isn't neutral is a waist of time IMO - interesting to talk about but ultimately a black hole for your time. We are all trying to achieve a sound the we - individually - like so there can never be one truth about any of this stuff. Just groups of people who cluster together at different points of the spectrum of what they consider correct. We all intuitively know this but I guess we are gluttons for punishment cause we keep going in circles about it. 😜 |
Al I agree with all your points. I want my recorded music to convince me it's live, warts and all. So I want it to be neutral and accurate. If it sounds any way all the time, even smooth and relaxing, that is not a good thing to me. Its not good either if the sound is continuously irritating and chases me out of the room. Its OK if some recordings are and come out that way. I know all is well when I hear a lot of variety and want to just keep on listening rather than wanting to turn it off. Only in recent years have I achieved that. |
Hi Mapman, Yes, consistent with Ralph’s response it’s certainly true that our hearing mechanisms do not respond equally to all frequencies. And as shown in the chart you referenced their deviation from flatness is different at different volume levels. And so distortion components, noise components, and deviations from flat frequency response will be objectionable to a degree that varies widely depending on where in the spectrum they occur. But an obvious point that nevertheless seems worth stating is that our hearing mechanisms have the same characteristics, including lack of flatness, when we listen to live music as when we listen to our audio systems, at least if volume levels are similar. So while an understanding of the hearing characteristics you (and Ralph) cited can be important in prioritizing the kinds of distortions and colorations that are most important to minimize, we also don’t want to have the system introduce colorations (i.e., deviations from neutrality) that "correct" our hearing. Assuming, of course, that our hearing is functioning normally. As you said earlier in the thread, "if neutral = accurate then sign me up." Best regards, -- Al |
The human ear is tuned to be the most sensitive at bird-song frequencies. It also uses higher ordered harmonics to calculate how loud a sound is- its not doing that from the fundamental frequencies as such are quite rare in a pure form in nature. So if the system generates these harmonics (5th and above) even in trace amounts our ears are so sensitive to them that they will be heard, even though the distortion of the amp might be 0.005% THD. The converts distortion into tonality. So the presence of these distortions is heard as both brightness and harshness (the 7th in particular having been known since the 1930s as a source of a metallic coloration), even though on the bench or in the room the system might measure perfectly flat. In fact the ear has tipping points wherein tonalities created by distortion can be favored over actual frequency response errors. So in some cases its better to have none of these distortions rather than perfectly flat frequency response. |
Al, my understanding is that perceived brightness has to do with the fact that our ears do not have flat frequency response and are more sensitive to some frequencies than others, and that some forms of harmonic distortion tend to attenuate those frequencies that we hear best and are more sensitive to. So the lack of "neutrality" of our ears are as much a factor as that which comes out of the transducer. Here is a link to the chart I’ve referenced many times (and I have framed and hanging in my listening room, a nice audiophile work of art and science) that shows at what frequency music things occur and the corresponding sensitivity of the human ear: http://www.independentrecording.net/irn/resources/freqchart/main_display.htm So for example if the system is perfectly flat or "neutral" what we hear is not. We will hear more of the frequencies that our ears are more sensitive to than the others which might be considered a natural colorization that we all share to some extent. How each individual reacts to that in terms of musical enjoyment, fatigue, etc. may in fact vary widely, which would account for why there is little agreement on what sounds "best". The studies Ralph cites on how humans hear may be consistent with the idea that the frequencies that our ears are most sensitive to are the most important ones in regards to listening pleasure and minimizing "fatigue" in general. But it does not mean that what is most "neutral" or flat" coming out the speaker will necessarily sound the best to many. |
Last_lemming 02-02-2016 5:04pmDracule1, brightness, bass heaviness, or other deviations from neutrality that may be perceived as frequency response anomalies are also not necessarily measurable in a manner that is practical or meaningful. First, as Ralph (Atmasphere) has often pointed out, perceived brightness is often caused not by frequency response errors, but by trace amounts of certain forms of distortion. Second, a microphone and its associated instrumentation will not interpret arrival time differences between various frequencies, or multiple arrivals of the same frequencies, in the same way our hearing mechanisms do. Arrival time differences occurring as a result of both room reflections and the fact that most speakers are not time coherent. So what may be perceived as a frequency response anomaly is not necessarily any more readily measurable than the other kinds of sonic issues you referred to. Regarding Last_lemming’s underlying point, I of course agree, as it is consistent with what I and Wolf_Garcia said earlier in the thread, as well as with what I quoted from Bryoncunningham’s post of several years ago. Regards, -- Al |
"geoffkait may be one of those people who believe math and science are intuitive. Perhaps - for real math wizards - it is intuitive. But for most of us, it isn't. Even Einstein said he struggled with math. It's probably futile to try and explain this to geoffkait, although atmasphere deserves kudos for trying." i do not believe math and science are intuitive. I am actually a big believer in experimentation. An experiment is worth a thousand words. Am I an experimental physicist? Probably, although my education was theoretical physics. I'm with Einstein, I'll let others do the math. But I know what numbers mean. |
Last_lemming, to be more objective why don't you just measure the frequency response of your system at your listening position? If you're concerned about something bass heavy or tilted frequency, that is easily measured. It's harder if not almost impossible to measure something more subjective as sound staging, imaging, or palpability. |
I tend to describe a neutral set up based on hearing many different "albums". If they all sound unique, meaning if some recordings sound bass heavy, some bright, some just fine then I figure the system isn't tilting the frequency in any one direction. I would call that system neutral. However if everything sounds bright well it's obviously not neutral. |
geoffkait may be one of those people who believe math and science are intuitive. Perhaps - for real math wizards - it is intuitive. But for most of us, it isn't. Even Einstein said he struggled with math. It's probably futile to try and explain this to geoffkait, although atmasphere deserves kudos for trying. |
@Al- The Dunning-Kruger Effect is another possibility. (https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect) The initial propositions, not the corollaries. |
The shielding in cables protects the cables from external radio frequencies but does nothing to protect the audio signal from the induced magnetic field. And the reason is because the induced magnetic field is a different issue and requires a different solution. It's name is high permeability.Again your first sentence is correct but what follows is not. One reason balanced lines work is because the system is relatively impervious to induced magnetic fields. This is because the magnetic field is impinged on the shield of the cable and the two conductors within. Since the shield carries no signal current whatsoever there are no worries there- it can't induce noise in the ground plane since ground is ignored. The internal connections carry the signal in two phases, 180 degrees opposed. When it arrives at the input (amplifier) the Common Mode Rejection Ratio (CMRR, https://en.wikipedia.org/wiki/Common-mode_rejection_ratio) of the amplifier then comes into play. If properly designed, the result will be that EMI imposed by the magnetic field cannot get amplified. This is because the input of the amplifier is looking for what is **different** between the two input signals and the EMI is the **same** to both inputs. Because the amp is looking for what is different, EMI gets rejected. The result is that the cable plays little or no role in the overall sound of a system. There are other factors that contribute to why this is so that have not been discussed. I find it quite odd that this technology has existed now for close to 70 years but still gets a lot of resistance (if you will pardon the expression) from audiophiles; eliminating cable interactions is a big part of obtaining neutrality in an audio system. I was designing satellite systems when you were wearing bell bottoms.It could be that you know so much that you have forgotten more than I will ever know. That *could* explain your lapse of basic communications knowledge essential to satellite technology. But Occam's Razor https://en.wikipedia.org/wiki/Occam's_razor suggests a simpler explanation. |
Geoff I think you are a control freak and exhibit symptoms of narcissism. Some megalomania perhaps to. It seems to affect your reading comprehension and ability to comprehend or accept anything anyone else says. Its all about you it seems. It might still be treatable. Try some humility or at least maybe thanking people when they correct you or try to help. Does not have to be me. And don't give up on the thought of maybe developing a conscience. Yes you might find it interesting. Just my constructive feedback based on observation. Not a personal attack. |
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"If what you are attempting to claim was actually true they would need repeaters every twenty feet as opposed to every 25 miles or whatever. When transmitting to a satellite at 23K miles there are no repeaters! Hel-loo!" That’s what Parabolic Reflector Antennas are for, in BOTH transmitting and receiving RF https://books.google.com/books?id=zIuiupZBcqkC&pg=SA5-PA28&lpg=SA5-PA28&dq=parabolic+in+transmitting&source=bl&ots=TlEm2J_VD0&sig=PgM6zc7uHCBjmeaW5dOTTM3uCqw&hl=en&sa=X&ved=0ahUKEwjV-uanstnKAhUC9WMKHb41AtMQ6AEIRDAG#v=onepage&q=parabolic%20in%20transmitting&f=false . |
Back to the topic of neutrality, I agree shooting for neutrality is a good thing. Lab measurements are a useful tool. Lower noise and distortion is always better. How one connects to the music emotionally and why is a very subjective thing. Neutrality may or may not be part of that. Regarding my own voyage along these lines, I feel I have achieved a good place in regards to neutrality and low noise and distortion with greatly diminishing returns for pushing any more forward there. I am interested in other approaches now and comparing. Ones that are more purely "subjective" in terms of being able to connect to the music. I have a pair of decent efficiency speakers (Triangle Titus) that I would love to try of a low power and not necessarily expensive tube integrated amp. Something along the lines of GLOW Amp 1, Jolida FX10, or maybe Decware. I’ll be replacing rotted surrounds on an old pair of Boston A40 speakers soon. I may try these as a stand in for the Triangles in order to free the Triangles up for a new system to experiment with. I have a large nicely finished but acoustically lively living room dining room area with no sound in it currently, and I’m thinking a small setup like this for more casual listening would work well. |
Al wrote, "I did not and do not express any opinion about the effectiveness of shielding with respect to magnetic fields. I don’t feel I can comment on that question in a knowledgeable manner without devoting more time to studying it than I care to devote." No problem, Al. But that’s what the discussion happens to be about. I hate to judge too quickly but it appears I'm the only one here with actual experience in controlling magnetic fields, the induced magnetic fields in cables, power cords and transformers. |
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What does all that have to do with the price of spinach?Geoff, in case it wasn't clear my last post was in direct response to your contention that: Radio waves do not follow the inverse square law like magnetic fields. If they did we would be unable to talk to astronauts on the moon or to send transmissions out into the galaxy you know SETI and all that. Radio waves don’t attenuate in vacuum of space and the only reason they attenuate in free space of Earth’s atmosphere is because of losses due to absorption and scattering....I did not and do not express any opinion about the effectiveness of shielding with respect to magnetic fields. I don't feel I can comment on that question in a knowledgeable manner without devoting more time to studying it than I care to devote. Regards, -- Al |
What does all that have to do with the price of spinach? The shielding in cables protects the cables from external radio frequencies but does nothing to protect the audio signal from the induced magnetic field. And the reason is because the induced magnetic field is a different issue and requires a different solution. It's name is high permeability. But I repeat myself. You guys can’t seem to see the forest for the trees. And for transformers the (induced) magnetic field is an even bigger issue. And manufacturers apparently do precious little about it from what I can see. It's almost like they're oblivious. The electron tubes are usually sitting right out in front on those big old transformers. Like sitting ducks. |
