If it's a '57 300C, I want one. |
Really, Geoff. Is it not legitimate to ask questions about such a claim (the notion that certain crystals can absorb RFI or EMI to a significant degree that would result in an audible effect in the average living room)? Or is it you, in fact, who wants audiophiles to behave not like high-schoolers but like pre-schoolers? "Open up wide now, and eat your crystals." I don't say it can't be true, but there must be some support for it in peer-reviewed scientific literature, if it is true. I can find none. Or are you also saying that science has nothing to offer in these matters?
And to those who hear a difference (Perditty): Be aware of the power of the placebo effect. A good test would be to bring a friend into your listening room who has no idea what the subject is, and test him or her for differences in sound with vs without the crystals. By the way also, RFI is detectable, and a reduction in RFI should be measurable. |
Perditty, I meant no slur. Sorry.
Geoff, There has been a LOT of published science on the behavior of crystals in electronic applications. It's actually quite an interesting history dating back to the 1920s. By WWII, quartz crystals were already being used in the defense industry in electronics, and since the method for growing such crystals in a lab had not yet been developed, natural quartz was highly prized and sought after. There is no occult force in commercial audio that could or would suppress research into this area or any other area of science. You greatly exaggerate the power of the industry, and/or you don't quite understand how basic research comes to be done. I have to think that if free (meaning "not in-circuit") quartz crystals (or any of many other kinds of crystals now available) could absorb RFI, there would be a published paper describing this phenomenon. On the other hand, I agree that my failure to find the papers (so far) is no proof that such work has not been done. I will keep looking. There are EEs lurking here. Perhaps one of them knows. |
Geoff, I sense your sarcasm, but I am immune to it. Another computer search today reveals mainly that Google finds either confirmation from many sources that crystal oscillators are a source of RFI OR it finds references in the Tweakers Asylum and elsewhere in audio fora, many of which are to your past postings, when I search on any combination of words that include "crystal" and "RFI". I see that you previously denied the probability that Cardas Caps block RFI from entering into an audio chassis, and on Tweakers Asylum you wrote this in 2010:
"I therefore propose there must be some other mechanism in crystals, when used individually or in groups - besides piezoelectric effect - responsible for the change in sound -- at least when discussing RFI/EMI absorption. I also propose that - in almost all cases - the actual operation of a crystal or group of crystals in an audio system has nothing whatsoever to do with RFI/EMI absorption - rather acoustic/mechanical energy absorption!"
So, we agree (because it's come to be my view as well) that crystals are unlikely to have a beneficial effect via blocking or absorbing RFI, unless you've changed your tune in the past 3 years. |
Forgot to add a response to Stringreen: This is not about whether crystals "work" or not. This is about the simple question of whether a crystal can absorb and eliminate or reduce RFI or EMI, at all, to any extent. |
I don't want to get into this too deeply on a personal level. I have known Lloyd for years, and I like and respect him highly. In my experience, every one of his tweaks works, but I have not tried them all (as you can tell vis crystals). I think his turntable is one of the finest I have ever seen or heard. The Walker Motor Controller, which I do own, made a sea change for the better in the sound of two of my turntables. It is difficult for me to engage in this discussion without seeming to be disrespecting Lloyd, but I assure you that is not my intention. So Benjie, do you think Lloyd can refer me to a paper in the scientific literature that describes absorption or dissipation of RFI by inert crysals? If so, I will call him. It would behoove him or anyone else making such claims to post the supportive references. I don't by the way deny that you or Geoff hear differences with crystals in or on or near your equipment; I am only wondering whether the given explanation holds water. In other discussions and on other websites, crystals are said to act by controlling "resonance" (as Geoff says in the quoted passages), not by absorbing RFI. Who can argue with something as vague as "resonance control"? Not I.
Geoff, you did write, "I also propose that - in almost all cases - the actual operation of a crystal or group of crystals in an audio system has nothing whatsoever to do with RFI/EMI absorption - rather acoustic/mechanical energy absorption!" I guess you can cling to the fact you used the word "almost". |
Benjie, Why don't YOU call Lloyd and ask him, and then tell us what he says.
Bruce, Everyone knows that a pyramid blocks RFI. That's why the Egyptians built those huge ones. The Pharoahs were buried with kick-ass audio systems. |
Perditty, Rodman, and Benjie: Can you get it through your heads that my question is not whether your system sounds better with the Walker crystals. It is also not about whether my system would sound better if I were to employ them. My ONLY question is: do crystals absorb or dissipate RFI, as claimed by the vendor? So far, I can find no evidence in the scientific literature to support that claim. This is not to say that you cannot go on enjoying the perceived effect of your crystals. I cannot understand why you respond with anger and/or sarcasm to the simple question I posed. |
Perditty, The only thing I would take issue with is your use of the term "debate". Inert crystals either can or cannot affect RFI. The debate could be about whether they make an improvement in one's audio system; that would be a reasonable subject for debate. |
Dear Neetzshe, You wrote:
"That is how science works: theory, then, experiment."
It can also work the other way: Experiment, then formulate a theory based on actual data. Then do more experiments to determine whether your theory holds water.
Please don't lecture to me on how science works; I have been a scientist for 40 years and have published lots of papers in first rank journals. Now just show me the data that corroborates the hypothesis that crystals attenuate RFI, and I will be happy. Also, please actually think while you read my previous posts on this subject. I never claimed that the tweak has no audible effect or that its proponents were nuts or laboring under a deception. I am only asking whether or not this effect that they do hear could possibly be due to attenuating RFI. |
Dear Rodman, The crystal in those old radios is an RF generator, not an RF absorber. In the old days, I think those radios were "tuned" to a particular frequency by changing the crystal, each one of which resonated at a different frequency. In fact, every time I tried to do a search on crystals as an absorber of RF, I got a list of papers documenting the fact that an electrically energized crystal (not an inert crystal glued to a tonearm) will radiate RFI. |
Also, if what you theorize were true, we wouldn't be having this discussion; it would be common knowledge. |
Dear Rodman, I assume that I am "Mr. L". If so, please tell me how your last post in any way addresses the question of whether an inert crystal (not one that is energized in any way) can prevent RFI from affecting one's vinyl playback. Yes, Al pointed out another way in which crystals are/were used in radio, but that does not resolve the issue. I read the relevant literature in my search. When a crystal is excited by RF, it does not remove the RF from the environment; it samples the RF selectively for its particular resonant frequency and then resonates, or not, as I see it. |
Dear Tawa, I guess your subjective opinion that the crystals make your system sound better makes it just "silly" to question how they might actually work, in the light of the claim that they absorb RFI. |
Dear Phduncanson,
Your URL leads to a white paper on RFI. No one doubts that RFI can be a problem in audio reproduction and that eliminating RFI is desirable. If you read the paper yourself you will see that the only way in which crystals are connected to RFI is by the fact that devices that use crystal-referenced oscillators, like the wrist watch specifically mentioned, radiate RFI. The article does not support the contention that crystals shield from RFI.
I am prepared to believe that crystals are beneficial, but I remain to be convinced as to mechanism for that, and that it even has anything to do with RFI. |
Dover, You wrote, among many other things, "The piezoelectric properties of a quartz crystal make it usable as a resonator." With all due respect,and I do respect you, as I understand it, a quartz crystal (or any crystal) when energized by electricity will indeed resonate at a unique frequency. That's what makes it so useful in servo and clock mechanisms. Along with this resonance, RFI is emitted. In this case, as I see it, RF noise and EM noise would be synonymous, but,when we just mount a crystal out in space on a cartridge or tonearm there is no electrical energy source to set the crystal into resonating, and I don't know how "the EMI emission from the crystal can alter the behaviour of other EMI floating around in the vicinity", even if it were emitting EMI/RFI. These frequencies don't shut each other down or interfere with each other very much except to re-enforce each other. Otherwise, we would not have radio stations broadcasting on adjacent bands that don't differ much in frequency.
And, as Geoff pointed out, I don't think this is "piezo" effect, for which pressure on the crystal is required.
Wasn't there also a ZYX cartridge that had a spherical sapphire-colored something mounted forward of the body? Was/is that supposed to be a crystal?
I am beginning to think I have to try this stuff, even though I would say the jury is out on how crystals may work. |
One effect of putting a crystal, or anything with mass, on a tonearm or cartridge is to alter the... mass. This can always be expected to have an effect of some kind. So, on that basis alone, no wonder it is common to hear a "difference". Has anyone done the following control?: Take a pebble or something of equal mass and affix it where you have previously heard a difference with the crystal. Then play a record and listen. On other grounds, I have come to think that most low compliance LOMCs can benefit sonically from an increase in tonearm effective mass, compared to the effective mass of the typical modern high-end tonearm, most of which are medium mass, at best. Just a thought. |
