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Mod Kyudan  |
MIT Cables white paper
http://www.mitcables.com/technology/power1.asp Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
http://forums.audioreview.com/showthread.php?t=708
skeptic Senior Member Registered Member Join Date: Feb 2002 Posts: 363 Quote: Originally Posted by pctower "Through the use of the power factor, we at MIT have been led to conclude that a poor power factor is a mechanism for distortion. That is, that networks exhibiting poor power factor transport and play in-phase music along with out-of-phase music simultaneously. What level of this distortion is audible? We are continuing our research in this area." This is a technical paper ONLY in the eyes of non technical readers looking at advertising copy. All of the technical explanations about impedence, capacitance, inductance are AC electricity 101 to an electrical engineer. There are some factual errors; "Since a High-End audio cable is typically constructed with many coils of wire, constructing a cable is like constructing an inductor. In fact, it is during the winding process that the important element of inductance is added." Actually they are constructed with many STRANDS (not coils) of wire but they are each pulled off coils in the cable assembly plant. Series inductance of the overall cable is the result of the geometry of the oveall cable meaning the diamater of the aggregate conductor and the spacing between them. Power transfer for signals fed through interconnects is insignificant probably at most in the microwatts if not nanowatts. If power or voltage transfer of an interconnect were a consideration in audio cables, they would cause enormous distortions in video signals fed through them because they require 300 times the bandwidth. They don't. Power factor changes created by a few feet of lamp cord to power equipment is virtually insignificant and probably not even measurable. Power factor changes to loudspeaker loads by "normal" speaker cables such as zip cord are undoubtedly insignificant. MIT says you have to have the right mix of inductance and capacitance? What is the right mix? Every loudspeaker load is different and most are highly inductive. If there was a right one for one speaker, it would be wrong for another. If there was a right "mix" created for a certain cable of a certain length, it would be wrong if you used a different length. If the wire had the right inductance stretched out, it would be wrong if it were curled up. The graph is virtually worthless. You can't see a thing. Comparative data on a chart would have been better. MIT's claim that some cables such as zip cord do not allow efficient transfer of low frequencies presumably because of power factor is not borne out by experience and there is no data to support it. Changing the power factor to a load not only depends on the impedence of the cable but the impedence of the load. Compared to loudspeaker loads, inductance and capacitance of most cables are insignificant. This concept of power factor is no different than the concept of LCR changing frequency response except made more complicated by stating it differently so it sounds like something new and different. There are no double blind tests to show that there is any audibly detectable difference between their cable and others. There are no waveform capture photographs or computerized analysis to show that there is any difference between current or voltage waveforms transmitted through their cable and anybody elses. There is not one single objective fact or suggestion of a fact to justify the purchase of their very expensive product in preference to much cheaper alternative. BTW, what the hell is "in phase and out of phase music"? I never heard of such a thing. The phase angle of non periodic waveforms typical of music always varies all over the place. Nothing new there either. It all sounds to like technobabble smoke for suckers. This is what they produce because this is what the law allows. Suggestion, inuendo, hypothesis, complex irrelavent facts, but no actual claims. Example; "Power that is not transported in phase may still be transported to the load. But it will be out-of-phase power." The concept of reactive power is of some use to industrial power distribution engineers like me, because some users eat up utility company amp capacity on transmission lines without using up watts. Beyond a point, some utilities charge extra for low power factors and so there are industrial means to deal with it (large power factor correction capacitors.) But it has no relevance or meaning here. Just there to impress and confuse prospective non technical customers. BTW, I'm not picking on MIT. They each have their own way of doing exactly the same thing. Each different, each worthless. Buyer beware. (Sofsoldier, I am an electrical engineer.) Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Expensive cables
http://forums.audioreview.com/showthread.php?t=708 Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Speaker Wire - A History by Roger Russell
http://www.roger-russell.com/wire.htm Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
E Stat's comments - 5 different articles regarding cables
http://db.audioasylum.com/cgi/m.pl?forum=prophead&n=2386&highlight=edgar+villchur+E-Stat&r=&session= Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Is a heavy guage power cord helpful?
http://forums.audioreview.com/showthread.php?t=1990&page=2 Dan Richards The Listening Sessions The Project Studio Handbook |
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Web References
Pease, Richard A.; "Understand capacitor soakage to optimize analog systems." http://www.nsc.com/rap/Application/0,1570,28,00.html Jung, Walt & Marsh, Richard N.; "Picking Capacitors", http://www.capacitors.com/pickcap/pickcap.htm Note on Cap D-E curves, by Steve: http://members.aol.com/sbench102/caps.html Karl A. Weber, "On Capacitor Dielectric Materials - A Chemist's View" http://audience-av.com/on_capacitor_dielectric_material.htm Comment: The previous four URL's relate to the capacitance of an audio cable. Goudreau, Pete; "JPS Labs Superconductor Interconnects: A Technical Discussion", SoundStage, http://www.soundstage.com/articles/pete01.htm Comment: A very interesting article on how chassis potentials affect interconnects. Hawksford, Malcolm Omar; "The Essex Echo 1995" http://free.polbox.pl/m/mik0/essex.htm Cardas, George; "Cable Resonance is Easy to Measure", http://www.cardas.com/insights/measureresonance.html Bond, Matthew; "The Science of Cable Design", http://www.sonic.net/soundscape/cable_ar.html (Parts 1-3 of this series appear in Stereophile Vol. 19, Numbers 1, 3 & 5.) Also at: http://www.taralabs.com/white_papers/Science_Design1.asp Magnan, Jim; Whitepaper on skin effect and time smear: http://www.magnan.com/buffs.shtml On Skin Effects in cable: http://www.femlab.com/electro/gallery/skin-effect.html http://capella.dur.ac.uk/doug/noisecols13.txt (Section 6.12) Conductor technology and info ala Van Den Hull: http://www.vandenhul.com/artpap/hybrid.htm http://www.vandenhul.com/artpap/brickwal.htm http://www.hometheaterhifi.com/volume_7_4/audio-cable-shootout-part-1-12-2000.html Whitepapers from Tara labs: http://www.taralabs.com/papers/index.htm Vandersteen on biwiring: http://www.vandersteen.com/pages/Answr7.htm Q&A on cables from Straightwire: http://www.straightwire.com/qa.html AudioQuest Cable Theory pages: http://www.audioquest.com/theory/theory1.html thru http://www.audioquest.com/theory/theory5.html MIT measurements on cables: http://www.mitcables.com/pages/page69.html must click onto the proper links to papers and tech info. Nelson Pass on speakercables: http://passlabs.com/spkrcabl.html OR http://passlabs.com/articles/spkrcabl.html Sullivan, Charles R.; "Optimal Choice for Number of Strands in a Litz-Wire Transformer Winding", Paper presented at the PESC '97, Technical Program, Plenary Session 1, Monday, June 23, 1997, St. Louis MO http://www.dartmouth.edu/~sullivan/litzwire/litz.html Comments: Has sections on skin effect, proximity effect, etc. More on Litz wire http://www.wiretron.com/litz.html http://www.soundstage.com/maxdb/maxdb011999.htm On cable resonances. Tag McLaren on cables: http://www.tagmclarenaudio.com/dev/white/wp_cables.zip (It's a huge 4 Meg+ file) OR http://www.tagmclarenaudio.com/dev/white/wp8.asp AND http://www.tagmclarenaudio.com/advice/technical/aug/aug.asp Empirical Audio website: http://www.empiricalaudio.com/ (has some interesting FAQ's and White Papers) Copper Crystal Structure microphotos http://microstructure.copper.org/coppers.htm http://microstructure.copper.org/grain_size.htm AND http://www.harmonictech.com/techgraph.htm Details on the processing of ETP copper: http://innovations.copper.org/metallurgy/wiremetallurgy.html More copper info at: http://properties.copper.org/ http://properties.copper.org/atomic/homepage.htm Visualizing electromagnetic fields: http://physics.syr.edu/courses/vrml/electromagnetism/ Computing basic cable parameters, while varying geometry and dielectric and conductor sizes: http://www.mogami.com/e/cad/electrical.html Info from Ragnar Holm Conferences on Connector aspects: http://www.ewh.ieee.org/soc/cpmt/tc1/index.html http://www.ewh.ieee.org/soc/cpmt/tc1/h2000top.html http://www.energy.sintef.no/ICEC/PDF-filer/9_5.pdf *Belden Cable Company* Cable Part Finder & Number Search http://bwccat.belden.com/cgi-bin/ncommerce3/ExecMacro/BELDEN/frames.d2w/report Tech article about Cable Impedance http://bwcecom.belden.com/college/Techpprs/ciocahalf.htm Belden Cable College: http://bwcecom.belden.com/college/college.htm Recommendations for Home Theater and High-End Audio by Belden/Steve Lampen (note: these recommendations are more casual than my own, and do not take materials issues as seriously. They may not coincide with my own recommendations, and are based more on the old school of cables as mere plumbing and RF carriers.) http://bwcecom.belden.com/college/Techpprs/rhtheatp.htm Belden Distributor Locator The Belden distibutor locator is now buried in their web site, see: http://bwcecom.belden.com/sales/sales.htm then click on Contact Information, and then on Distributor Locator Audio/Video Specialists Distributors (NOTE: May not carry 89259, or other coax or CAT5 cables, as these are not considered AV cables.) http://bwcecom.belden.com/sales/Distloc/AVdisloc.htm Cable Permitivity, Conductivity, and Permeability, from Gore web site: http://www.goreelectronics.com/products/emi/electromagnetic_material_character.cfm http://www.nationalwire.com/cdg/basicintro.html Good article for cable parameter basics. Blind tests of Speaker Cables, Home Theater mag. http://www.sonic.net/soundscape/wire_rev.html http://www.ozenterprises.net/wire/icacbles.pdf Web site with lots of info on capacitors. http://www.faradnet.com/ E-book on Electrolytic capacitors, includes basics of capacitors. http://www.faradnet.com/deeley/book_toc.htm http://www.faradnet.com/deeley/chapt_01.htm Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Current Dependent Phase Shifts in Audio Cables?
http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/cableshift/cp.html References [1] The Great Cable Test – Part 1. Harrison, A., & Duncan, B. Hi-Fi News & Record Review 30-41 44(7) July 1999 [2] The Great Cable Test – Part 2. Harrison, A. & Duncan, B. Hi-Fi News & Record Review 32-41 44(8) August 1999 [3]The Great Cable Test – Part 3. Harrison, A. & Duncan, B. Hi-Fi News & Record Review 40-53 44(9) September 1999 Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Audio Cables - Fact & Fiction Revealed
http://www.ecoustics.com/bbs/messages/5/6528.html Dan Richards The Listening Sessions The Project Studio Handbook |
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Watch Dog #10
Ten Big Lies From The Audio Critic http://216.239.41.104/search?q=cache:K4ZDBoYNgaoJ:www.audioperfectionist.com/PDF%2520files/watchdog10.pdf+ac+power+cord+abx&hl=en&ie=UTF-8 1.) The Cable Lie Aczel states that cables are “not primary audio components” but merely accessories. He says that those who claim high-priced audio cables sound better than Radio Shack cables are lying. The only cable parameters that affect per- formance are resistance, inductance and capaci- tance, according to Aczel. Here’s a quote from The Audio Critic: “A nice pair of straightened-out coat hangers with the ends scraped is not a whit inferior to a $2,000 gee-whiz miracle cable. Nor is 16-gauge lamp cord at 18¢ a foot.” While different cable designs may indeed exhibit differences in measured resistance, induc- tance and capacitance, the conclusions drawn here are absolutely false and you don’t have to take my word for it. I’ll tell you how to find out for your- self without relying on any “expert” advice. Where’s the kernel of truth here? The truth is that there are some cynical and corrupt individ- uals in the high-end audio cable business and some of their products have little or no merit. Is high-end cable often overpriced and obscenely profitable? You bet it is. Is some of the most expensive cable actually highly colored and less accurate than Radio Shack wire? Absolutely. Can we conclude from these facts that high quali- ty cable is worthless and that everybody in the cable business is perpetrating a fraud? Of course not. While there are indeed some charlatans in the audio cable business, there are others who are genuine enthusiasts striving to improve the sound of the audio systems in our homes. Some of these individuals are highly qualified engineers who know that there is more to wire than R, L and C. In fact, transmission lines that work at audio fre- quencies, where the ratio of frequencies is enor- mous, are particularly difficult to design. There is, of course, objective evidence of this and readers of the Audio Perfectionist Journal will be able to view square wave tests and transfer function graphs of various cable designs in future issues, but everyone can listen and hear for themselves without resorting to testing of any other kind. Ivory tower theorists can “prove” that a bumble bee can’t fly but you can gather empirical evi- dence, through observation, that their proofs are wrong. Aczel can say that a coat hanger is electri- cally equivalent to a well-designed audio cable—a falsehood that can be refuted by objective test- ing—but your ears can recognize that the two don’t sound the same. You can hear the sonic effects of intercon- nect cables by doing a simple bypass test. Speaker cables can be compared, one to another and to lamp cord. If you listen with an open mind you will likely discover, as I have, that all cable degrades the signal somewhat. Better cable simply causes less damage. Here’s how to hear the effects that cable has on sound quality. Directly compare one set of cables to another and to a bypass jumper. David Salz of WireWorld makes a relatively (but not complete- ly) neutral cable comparator. WireWorld dealers can directly compare one set of cables to another using this switching device while you listen. A third position on the switch inserts short solid copper jumpers into the signal path in place of the cables under evaluation. The switch is rotary and unmarked so the comparison will be double-blind. Of course, you can also listen to one set of cables for a while by yourself, and then switch to another for comparison. No comparator required, other than your own ears. A preamp with an unbuffered tape loop allows a simple bypass test for interconnect cables. Put a set of interconnect cables in the tape loop connecting the tape outputs directly to the tape monitor inputs. The tape monitor switch will now allow you to compare the sound of the cable to the sound of no cable (bypass). If your preamp or receiver has active buffers in the tape loop— and most do—the sound of these buffer circuits will be included with the sound of the cable, but the differences in cables can still be clearly heard even in a modest system. Compare one set of cables to no cables (the bypass). Then compare another set of cables to the bypass and see which set does the least damage to the music. Page 3 Audio Perfectionist Journal•Watch Dog #10 Copyright © 2001 R. L. Hardesty ------------------------------------------------------------------------ Page 4 Speaker cable is a little more difficult to evaluate but any dealer worth your business will demonstrate his wares for you and should be able to compare what he recommends to the competi- tion or to some standard reference like lamp cord or regular Monster Cable. A good dealer will let you take cable sets home so you can do these experiments in your own room with your own system components. Here are some simple facts which you can verify for yourself: Cables have a profound effect on sound quality. All cables degrade the signal to some degree but the best examples cause less damage to the music. The most costly cables are frequently less accurate and more colored than less expensive alternatives with better design. You’ll never achieve sound quality that rises above mid-fi mediocrity until you discover that cables are an essential component in a high quality audio system, not simply an accessory Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Designer Cables: A Critical Look
http://www.svconline.com/ar/avinstall_designer_cables_critical/ Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
What's All This Hoax Stuff, Anyhow?
http://www.elecdesign.com/Articles/Index.cfm?ArticleID=6134 As I warned you guys, April is a good time of year to write about hoaxes, and several people have sent me some neat ideas. But one guy asked, "Bob, what is the difference between a Hoax and an April Fool joke?" I told him that you can't tell from the way it starts out, but by the time you get to the end, a good April Fool joke should give you enough clues so you can start to smile. But if you're merely puzzled, or skeptical, that could be a hoax. Conversely, if the guy tops off his story with "and send money," that's a clue that it may be turning into fraud. But sometimes, the guy isn't aware that the situation is impossible. He has fooled himself badly, and may be unaware of the truth. So if you're just listening to the start of the story, or the end, you can't always tell. As I mentioned earlier, some of the stories about Fuzzy Logic start out like an April Fool joke, but after you figure out that the guy is serious, then it's only just funny. However, we have seen some claims, such as "only with Fuzzy Logic can an elevator avoid lurching." That's more like self-deception. Or, "The Sendai train is 10% more efficient than a train without Fuzzy Logic, and runs faster, too." That's a scream!! (Details available on request.) Back in October, I heard a good program about hoaxes on the radio and sent away for the Encyclopedia of Hoaxes that they mentioned on the show.1 It really is a pretty good collection of Hoaxes, April Fool jokes that went too far, etc. But, unfortunately, it doesn't include any hoaxes in the field of electronics. So after I publish this column, I'll have to send a copy to the author so he can include some of the following stories about hoaxes in electronics. Let me start out with the Tice Clock. This clock is a basic LED digital clock, substantially identical to a $30 clock sold by Radio Shack. But George Tice sells this for $270. He makes some very lavish claims that by plugging this clock into your audio amplifier's main 115-V power socket, the clock will make all your audio equipment sound much better—that is, if you have a "Golden Ear." However, if you can't hear any difference, then you're admitting that you don't have a Golden Ear—that you have only limited auditory capability to appreciate the BEST in audio. Many reviewers for hi-fi magazines have agonized over this. A few think it's great—the reviewer can really hear the improvement. Others search for any plausible technical reason for improvement. One reviewer observed, "If Mr. Tice enclosed a Negative Ion Generator in his clock, maybe people really WOULD think the music sounds better." But he had to concede that there was NOT any ion generator in there. So, many people have come to the conclusion that this clock is (at best) a hoax. They can't hear any difference, and there's nothing to measure. There's no subjective or objective reason to think that Tice's "clock" can make the music sound better. But it sure takes a lot of brass to make such claims. On the other hand, some people think that painting a green magic marker line around the circumference of a CD makes it sound better. Some people think that putting a new part number on an old op amp makes it sound better. Some people think that dunking a 16-bit DAC in liquid nitrogen for a while makes that sound better. Maybe you can hear the difference. I can't. Now, let me digress briefly. Let's say you have demonstration models of some good loudspeakers. How do you decide that type A is better than type B, or, that it's different? Mr. David L. Clark, Chief Engineer, DLC Designs, Farmington Hills, Mich., combined a set of relays and a random number generator to make an "ABX" tester. If you push the switch for A, the tester connects to the A speakers, or the A set of wires, or whatever. Then you can listen intently and decide that the sound you're listening to is the "A" sound. If you hit B, you get channel B, and you listen to "the B sound." If you push X, you get a randomized selection and you jot down whether it's channel A or B. At the end of 10 tests, let's say that you have listed: A, B, A, B, B, B, A, A, A, B. Once that sequence is completed, the ABX box will tell you what it ACTUALLY connected. If you listed eight out of 10 correctly, that's a lot better than just guessing—you probably did hear a difference. If it's four or five, well... Who knows? In some cases, some people with really good ears can hear things that I cannot. In other cases, they're unable to tell. In yet other cases, they refuse to try because they don't like the test. Still, when speaker cables of different types or characteristics are connected through an ABX box, some people with "really good ears" might hear the difference IF the wires have different amounts of inductance, capacitance, or resistance. It's generally admitted that no matter how exotic the materials or the construction techniques, if two sets of wires have the same R, L, and C, you can't tell them apart. Nobody can. So you'll find that one guy wants to sell you 10 feet of speaker cable for $100; another guy claims his are a LOT better, and they MUST be better because they cost $300 for 10 feet; and then a similar claim is made for a $480 cable. But if they all have the same R, L, and C—and each one spouts claims such as..."superior imaging"..."finer presence and less phase shift," etc., etc.—that strikes me as somewhere between fraud and hoax. You can spend your money any way you want to. You can say that you hear a difference. But if I offer you an ABX test, you should not get mad at me and stalk out. Some of my favorite "hoax" stories are just the claims that manufacturers of speaker cables tell about their wires. I really like the cable with "large-diameter wires to carry the low-frequency music, and small-diameter wires to carry the high-frequency music." (Of course, it's easy to compute that the skin effect of copper wire will make a 3° difference in the phase shift of the thin/fat wires at about 300 kHz. And, since the fat wires and the skinny wires are paralleled, you won't be able to see any significant difference in phase shift at 20 or 30 kHz.) The other cable I'm impressed with is the stuff that has a conductive "insulation." When this cable's resistive losses match the capacitive and inductive attenuation and the conductive losses, and the phase shift is minimized, it should sound better. Well, if it sounds better to you, go ahead and buy it. But, if it just sounds different, then maybe you do want to buy it—or maybe you don't. Maybe when you really turn up the volume, the conductive "insulator" will start to get hot?? Speaking of cables, my friend Tom said that his wife recently went to buy some new speakers at Circuit City. The salesman sold her some new speaker wires "because the old ones were probably worn out." Additional amazing audio quasihoaxes: a. When you have line-level cables (with RCA-type phono jacks), the expensive cables sound much better than inexpensive ones. b. After you decide to specify the expensive cables, the ones with gold plated jacks sound much better than the solder-plated ones. c. These cables have a preferred direction, and sound better when you connect them up in the preferred direction, with the arrows pointing from the tuner toward the amplifier. d. In addition, these cables sound better if they have been broken in, or aged, with a special ac signal forced through the cable. e. The best burn-in fixture for these audio cables uses digital signals to force current through the cables. Needless to say, I've never heard of any one of these wonder cables being tested with an ABX box. Probably the "Golden Ear" person would object to the relays in the ABX box, as they would corrupt the signal. But maybe we could overcome those objections by using a digital burn-in circuit to burn in the ABX box... The next area I'll mention briefly is the "vacuum tube sound." This isn't about a hoax, but rather a chameleon. It's well known that some audiophiles prefer audio amplifiers made with vacuum tubes. They claim that the ratio of 2nd-order harmonic distortion versus the 3rd-order is more pleasing with a good vacuum-tube amplifier. Maybe so. Myself, I've got a tin ear, not golden, so I'm not very picky. (Maybe I did too much chainsawing as a youth, or turned up the volume on Chuck Berry too many times.) But Mr. Carver, an excellent designer of audio equipment, came up with a beautiful ploy: He took one of his low-distortion solid-state amplifiers, and added a circuit with a little bit of 2nd harmonic to make it "sound like" a vacuum-tube amplifier. I'm not familiar with this amplifier's ABX comparisons, but I think it's a NEAT idea to make a chameleon amplifier like that. I think it's great to see if the Golden Ear guys can be fooled. About 30 years ago, when transistors did not have much performance, a contest was run to make a small high-performance audio amplifier. The late Peter Lefferts won the prize, with a small (6-in. cube) block and heat fins. Inside were a couple of small (6L6GB?) tubes running hot but with good heat sinking. They were legal under the rules, and nobody else thought of doing that. A friend told me about a promoter with this scheme: They had a conventional TV transmitter, and at the end of each cycle, just before the zero crossing, they would insert a brief pulse signal before the normal RF signal resumed. Then a specially designed receiver could detect those pulse signals and extract additional info. At 200 MHz, you could also get 200 Mbits/s, free, without any increase of the RF bandwidth. Further, this excellent communication scheme was backed up with a U.S. Patent and a big development company formed by a guy named Gerdes. As soon as I heard this line, I got VERY suspicious. My friend promptly admitted, "Of course, after a big press conference where this great technology was announced to the world, several engineers confronted the inventor and insisted that any studies showing you could do that without requiring more bandwidth were obviously malarkey." "The development company folded up... The promoter hasn't been seen since." Yes, that sounds like a hoax—or a marvelous example of self-delusion. These days, there are entirely too many cases where computer simulation leads an inventor to believe it will work... Gunnar Englund of Gransbergsdal, Sweden, once proposed some filters for line power that would filter out any electric power generated with nuclear power. He figured he could sell lots of them to environmental fanatics, with the guarantee that the output power will not show any nuclear residues. But then he got nervous about prospects of a criminal record, even though his guarantee would surely hold up. Here's another good hoax: Mr. H. told about a group of engineers at Northrup, who in the 1960s invented a "metric tensor sensor"—a meaningless non-invention with a melodious name. They even got a dummy patent application all drafted. Unfortunately, the senior manager signed it off and sent it to the Patent Office before anybody could explain. THEN they had some explaining to do... An engineer from Basingstoke, England, sent in a classy little pamphlet produced by Motorola (U.K.) showing a new non-electromagnetic telephone that used the scientific principles embodied in two tin cans and a length of string. VERY nicely done. They even had a rare-earth barrier to protect the inner "Lirpaloof" fiber from fiber-eating locusts. Jolly good. I have the Abstract of a U.S. Patent—a "Permanent-Magnet-Powered Motor".2 Of course, the Patent Office won't approve a patent on a perpetual-motion machine. But this one apparently snuck through. Then there's Joe Newman, who back in the 1980s invented a motor with very high efficiency.3 It's so efficient, he claimed, that it puts out more power than it takes in. Further, he claimed that he could run a car with no more current than a transistor radio needs. Of course, when engineers saw him loading 1800 9-V batteries into the car, all stacked up in series, they realized that such a battery can indeed provide a full 1/3 horsepower when loaded with 16 mA. If you have a motor that's designed to work at that high voltage, you can indeed move a car at a slow speed for a short distance, as Mr. Newman has indeed demonstrated. This was the guy who sued the Patent Office after they refused to patent his motor. When the NBS showed that his motor only appeared to put out more power than it took in, because he used an RMS voltmeter that couldn't accurately handle the low duty cycles and high harmonics that his motor ran on, he accused them of being incompetent at measuring things!! I've inquired about his progress at promoting his motor, and ran a literature search in our library, but nobody has heard anything from him for eight years. In a scheme with similar ramifications, Norman Dean invented, back in 1956, a machine to "rectify centrifugal force."4 First he set it up so that incoming rotary energy would cause some jerking motions. These could be synchronously detected by some clamps on a pole, which this apparatus could climb. Then Mr. Dean got the same basic scheme to run without the pole, just sitting in thin air! It could turn energy into force. He proved that it would do this because he could start it up on a bathroom scale, which would then start to read negative weight! Of course, nonlinearity of the scale mechanism was never considered. I first read about this in "Analog Science Fiction" magazine (which has nothing to do with analog circuitry), in which its masthead conceded that there wasn't necessarily a dot of truth in anything they published. Lovely!! However, Mr. Dean proposed a large-scale demonstration. Get four of these "Dean Drives," one on each corner of a nuclear submarine, and—presto—you have a nice little space ship! "Why won't the Congress give a fair consideration of my invention?" he bleated. My demonstration would be even more fun: get a couple of these "Dean Drives" running on the tips of a long rotor in a vacuum. You could put in 100 W, which would generate a certain number of ounces of force. Then, when you get the speed of the rotor up high enough, that few ounces of force would generate more power than the input power—thus, a perpetual-motion machine. Needless to say, this machine generated a LOT of controversy and head-scratching in its day. Let's mention computers (some people have suggested that almost any use of a digital computer can be considered a hoax ...). How fast can a computer display write? One well-known computer benchmarking program yields a result called a "Winmark." Part of the test originally consisted of repeatedly writing to the display: "The quick brown fox jumped over the lazy dog." However, some bright young guy figured out that if he set up a detector for that phrase, he could then shift into a hot-rod mode that couldn't handle anything else, but it could display that phrase really fast. His Winmark rating was much superior to anything else in his price range, until the trick was discovered. Then, every time a new task was set up, detectors would be told to search for the phrase and go into fast graphics mode. I think they finally gave up on that. But, that's exactly like the Corvettes that have come out over the last couple years: If you start out moderately in first gear and try to shift up between 16 and 20 mph, a computer predicts that you must be trying to do an EPA test, locking out gears 2 and 3 and forcing you to shift to 4th gear. With this ruse, passing the EPA tests is easy. If you want to defeat this lockout, just wind it out to 25 mph, and then you can shift into any gear you want, because the computer knows you're not an EPA guy. A couple of people told me about the young fellow who found a way to get much faster results in general-purpose computing by just adding a capacitor to the main board. Everybody was impressed with his excellent Whetstones! It took several days before some guy with a stopwatch realized that it didn't complete the task any faster—it just slowed down the clock for the task timer. The guy who had made a "lucky guess" did apologize—he really didn't know how he was being fooled. Bob Dobkin was at National in 1975 when he invented a Darkness Emitting Arsenide Diode. This had many features—light output never fell off with time, and they were cheap due to high yield. Just check the acronym. Then in 1979, Dobkin "invented" a BD-1, a Battery-Discharger circuit. You manufacture this by taking a TO-3 regulator that's dead, and cutting off both pins. Then the resistance from one bolt-hole to the other is about 0.9 m, and thus can be used to carry hundreds of amperes to discharge batteries, etc. ... He got a good paragraph write-up in the April 1 issue of an electronics magazine. We all smiled at that one. Then a few days later, I ran into Roy Essex, the marketing manager for power regulators. Roy was in a grouchy mood. I asked him why. He rambled on that a customer had called several times to get more information on some absurd Battery-Discharger chip, and he wasn't able to get any information about it, and the customer was getting madder and madder, and if there was any such chip, he should know about it, but he had no idea what the customer was talking about... I replied, "Roy, did he call that chip-the BD-l?" Roy spun around: "How did you know that?" I tried to explain that it was just an April Fool joke. That made Roy even madder. Then we realized that the silly customer didn't realize it was an April Fool joke, as he could not find where it was announced in the magazine. That really got him mad! Roy was mad at Bob Dobkin, and, it seemed, at the rest of the WORLD for several YEARS. Ham radio guys are always inventing and building equipment, so they're prime targets for pranksters. In 1966, Tom Kneitel published plans in S9 magazine for a small, low-cost antenna made of two 100- resistors. He claimed that, "It has the lowest possible VSWR across the entire band with a perfect match to any rig; exhibits an omni-directional null radiation pattern; eliminates adjacent channel overload from strong local signals; may be used either horizontally or vertically; completely ends TVI problems; is impervious to auto ignition noise; and has maximum efficiency at any height. Rust-, corrosion-, and lightning-proof, it can be carried around in your pocket for walkie-talkie use." Of course, many Hams built it and complained that they could not get this antenna to transmit or receive anything. Exactly... a dummy load. Other famous April Fool stories are about tall antennas that can't be seen due to use of stealth paint, etc. When Nikolai Tesla invented the ac induction motor in 1877,5 which ran with no brushes and no commutator, it was greeted with severe skepticism—must be a hoax. I'm sure if I had been there, I would have been incredulous, too. However, some of the later claims of Tesla border on the bizarre, and may fall over into hoaxery. Claims that electricity can be transmitted around the world with no losses, megavolt sparks under complete control, and an oscillator with an output of 10,000,000 horsepower were pretty wild, impossible to duplicate, and pretty hard to prove or disprove, theoretically or otherwise. Heck, that reminds me of the April Fool circuit that was alleged to cause the end of the world if turned on. Some guy wrote that he built it and pushed the button, but complained that the world did not end when he pushed the button. Tesla's ghost?? Because I'm not knowledgeable about Software, I will not have much to say here, except to quote from a News Release—Vogon News6: "In an announcement that has stunned the computer industry, Ken Thompson, Dennis Ritchie, and Brian Kernighan admitted that the UNIX operating system and C programming language created by them is an elaborate April Fools prank kept alive for over 20 years... 'As a lark, we decided to do parodies of the Multics environment and Pascal... We stopped when we got a clean compile on the following syntax: for(;P("\n"),R-;P("|"))for(e=C;e-;P("_" +(*u++/8)%2))P("|"+(*u/4)%2); "To think that modern programmers would try to use a language that allowed such a statement was beyond comprehension! We actually thought of selling this to the Soviets, to set their computer science progress back 20 or more years. Imagine our surprise when AT&T and other U.S. corporations actually began to use Unix and C!..." Beyond that, RAP has no comment. (Complete details available from RAP with SASE.) In another case of subterfuge, a friend gave me a copy of a Special Announcement: "After a long period of research and development, Mohawk Engineering announces a revolutionary new switch and charging system...which allows a battery system of any type to supply power to a load or device while automatically and simultaneously allowing the battery to recharge itself." Complete blueprints can be obtained for just $100 from a post office box in Springfield, Mass. Back in 1958, some engineers were quite unhappy about the quality of papers being published at conferences, so they wrote up a marvelous piece of puffery about their new "Linistor." This paper was accepted at WESCON. Then they revealed that their new invention was an alternate way to describe the resistor. Their prank had the desired effect when technical conferences began screening the papers more closely. Recently, a Reviewer was evaluating a "Scantrack 18 Golfball Finder"7. After diligent and fruitless efforts to find any "output" from this little $89.95 gem, which uses "new microchip technology" to detect the "molecular wavelengths emitted by golf balls," he got mad and X-rayed it, and found it completely empty. No circuitry at all. Wonderful hoax. What was the year—1978?—when Signetics brought out the WOM—the Write-Only Memory? Not just any simple April Fool joke, this marvelous invention was professionally presented in full color in a four-page foldout section of electronics magazines. Even us Analog guys got a good giggle out of that one! I've occasionally wondered what $ was paid for the publication of that fine joke—and by whom!! One does still see, in cheap magazines and on odd radio stations, advertisements for the little box that "turns your house wiring into a giant TV antenna." I asked my friends who are knowledgeable about TV and ham radio. One said it was just stupid, because it did all of the wrong things with the signals. Another guy said its theory was dubious, but actually he had seen it work better than a rabbit-ears antenna. Consumer Reports says this kind of antenna usually does more harm than good8—a bad investment for $1.99 in 1973, and a bad investment for $19.95 in 1994. At least one guy thinks that ISO 9000 is a first-class hoax. I will admit that we may be forced to conform to the minimum requirements of these regulations drafted by a bunch of European bureaucrats, in order to do business with Europe. However, I agree with George Lohrer of Programmed Test Sources Inc.9 that some of the zeal we see for super-compliance and "we can meet ISO 9000 better than you can" is pretty disgusting. Copies of his letter available from RAP per SASE. One of my readers spotted a case where a hobby magazine ran a build-it-yourself article. A special 24-pin IC, available from the author for just $30, was used to make an interface between a Macintosh computer and an ordinary video display. However, the actual circuitry inside this 24-pin IC was just a 7404 inverter IC, encapsulated with a funny pin-out. Ahem. Obviously, I don't know half of the good electronic hoax stories in the world, but, hey, we have run out of room, so we will just print what we got. If you know a better one, we may run it next year. Comments invited! /RAP Robert A. Pease/Engineer Dan Richards The Listening Sessions The Project Studio Handbook |
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Mod Kyudan |
Who Do You Believe?
by Greg Smith (gsmith@westnet.com) http://www.soundstage.com/articles/greg15.htm Dan Richards The Listening Sessions The Project Studio Handbook |
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