Digital Audio Myths - Listening on a PC

Done on mine

At last I found a good source of information - a page which describes both audiophiles and skeptics. I took the liberty of highlighting remarkable passages which I find remarkable and aggree with in red.

http://en.wikipedia.org/wiki/Audiophile

Audiophiles

• There are problems in applying double-blind methods to comparison of audio devices; audiophiles assert that a relaxing environment and sufficient time, measured in days or weeks, is necessary for the discriminating ear to do its work; further, that the introduction of the switching apparatus, involving as it does either another metal connection at the switch or another level of electronic processing with solid state switches, obscures the differences between the two signal sources being tested.
• While tubed electronics are less linear than solid state at high signal levels, they are claimed to be significantly more so at lower (sub-one-watt) levels; and it is argued that most musical signals spend most time at these levels. Paraphrased, "The first watt is the most important."
• Total harmonic distortion has been proved by scientific testing to correlate only poorly with perceived sound quality; the type of distortion is very significant. For instance, distortion by even harmonics has been shown to be less objectionable than by odd harmonics.
• In general, proponents of "high-tech" solutions (such as the earliest CDs) dismiss complaints of audiophiles on the grounds of the new systems' ideal behavior, rather than real world behavior using real world components. Often this is followed by the introduction of newer, improved components which are sold as lacking the problems of the prior generation, which had been described as "audibly perfect" at the time. For instance:
• In defense of their preference for analogue over digital formats, audiophiles point out that the process of converting a bit-stream to an analogue waveform requires heavy filtering to remove spurious high-frequency information, and that it should be expected that such filtering should involve some signal degradation and a large amount of phase shift in the passband. They point out that commonly used consumer grade digital to analog converters (DACs) exhibit very poor linearity at low levels. Both problems, at first dismissed, were then addressed by such solutions as digital filtering, oversampling, and use of 20 or more bit DACs. The introduction of the new higher-bandwidth "high-resolution" music formats was a tacit admission of the reality of this issue. Musician Neil Young, for example, was a harsh critic of the sound of the original CD format, but has approved of the sound of the Super Audio CD (SACD) with its greater "safety margin" between its ideal behavior and the requirements set by the limits of human hearing.
• Audiophiles were insistent on the sound degradation introduced by large levels of negative feedback in amplifiers, long before the universal acceptance of the fact that, while this technique was indeed beneficial to amplifier stability and test results using steady-state waveforms, it was inherently problematic for constantly changing waveforms as in real music, and resulted in amplifiers that tested well and sounded bad.
• Audiophiles were insistent on the improvement in sound quality they heard with higher quality capacitors (such as tantalum) in place of or bypassing large electrolytics or paper capacitors in the signal path, long before the universal acceptance of the fact that such capacitors, involving as they do significant inductance due to their spiral-wound construction, do interfere with passage of the highest audio frequencies.
• Audiophiles were experimenting with improved power supplies for CD players in order to block them as a path for the mechanical section of the CD drive and the digital section around the DAC to affect the audio section. In particular, the concern that voltage fluctuations in the power supply from the load of the motor would affect the internal digital clock of the digital section, and that such digital clock "jitter" would cause audible distortion was explored by audiophiles long before it was found to be valid by manufacturers.
• Although clearly audible levels of very objectionable distortion were demonstrated early in the digital audio era by simply running a signal source through an analog to digital converter and the result through a digital to analog converter, and electronically subtracting that result from the source, this demonstration was ignored by the digital audio proponents, much as the inability to demonstrate differences by double blind testing was ignored by the audiophile camp.
• Audiophiles were experimenting with room acoustics long before component manufacturers began to consider them a factor.
• Audiophiles noted the differences in response speed between various speaker drivers used in a single speaker system, and began experimenting with fewer drivers, stepped speaker boxes, and so on.
• Many vendors or retailers offer free trials, or money-back guarantees if their products are unsatisfactory, and they remain in business.
• Despite a lack of formal education, experienced "listeners" can be relied upon for objective advice on how equipment sounds, and whether its worth the price.

Skeptics

• There are reports of Double-blind tests which fail to support audiophile claims that they can easily perceive significant differences between very similar musical components.[1]
• Listening tests are notoriously unreliable; for instance, Edison showed that entire theater audiences were unable to distinguish between the sound of an orchestra or a playback by his recording system, which today would be regarded as ludicrously poor in quality. Similarly, early CDs and CD players were accepted as having fantastically great sound quality; those exact same systems today are regarded as fatally flawed, while analog systems from that period have not similarly fallen in public assessment of quality.
• Similarly, repeatability is poor for evaluation of components between various listeners, or even the same listener under different circumstances; this contrasts with the superficially similarly esoteric oenophile world, where repeatability of blind tests is surprisingly good.
• Measured audio distortion is immensely higher in electromechanical devices such as speakers than in purely electronic components such as CD players and amplifiers, making it hard to believe that subtle differences in the latter can have an appreciable effect on music quality.
• Similarly, acoustic behavior of the listening room, and the interaction between speakers and the room acoustics, is immensely more variable than variation between electronic components; in an electromechanical system such as a speaker, such interaction is reflected in the interaction between speakers and the amplifiers which drive them, so that the entire difference in sound quality between amplifiers is often postulated as merely either the ability to control the behavior of "difficult" speakers well, or else just a lucky combination of speaker, amplifier, and room which works well together.
• Minute differences in loudness have been demonstrated to be perceived as differences in sound quality rather than loudness, with the slightly louder system sounding better; so that tremendous care must be taken in matching sound level, using sensitive sound pressure meters, when comparing systems if the results are to have any validity at all; this is usually not done.
• Audiophiles often totally disdain all attempts to categorize differences in sound using instrumental measurements, despite the work of such combination audiophile-engineers as Bob Carver, who have repeatedly shown that by tailoring the transfer function of any system with a relatively simple sound-shaping network, they can make it sound indistinguishable from any other system, as requested.[2][3]
• Audiophiles often prefer the use of vacuum tube rather than more modern solid state electronics, despite their substantially-higher measured total harmonic distortion. When this is pointed out, they often claim that the distortion is "warmer" or "more musical" than that of a transistor amplifier. Interestingly, the relatively soft distortion characteristics of tube amplifiers are used regularly in high-end guitar amplifiers; in this case the loss of fidelity is intentional and even characteristic of the electric guitar sound, and transistor-based amplifiers are often frowned on for guitar use due to the harsh clipping artifacts created by a distorted transistor amp.
• Audiophiles regularly make strong claims for the superior quality of music reproduction from (vinyl) records on a turntable, compared to modern digital alternatives (which, among other things, are free from "click and pop" problems and background noise), even though compact disc audio in particular is designed to have a wider dynamic range than vinyl.
• Audiophile equipment designers can obsess over seemingly irrelevant details; for instance, the almost universal requirement to reproduce frequencies higher than 20 kilohertz, even though some kinds of equipment will not reproduce anything higher than 15 or 16 kilohertz (for example, FM radio and vinyl records).
• Some audiophile practices seem driven by fashion, such the late-Eighties vogue for marking the edges of CDs with a green felt marker, or the practice of suspending cables above the floor on small racks. Skeptics argue that the laws of physics are not subject to fashion.
• The prices of audiophile products can seem remarkably high, even if one believes in the benefit conferred. It is quite possible to spend over a hundred thousand dollars for speakers, and tens of thousands for amplifiers and CD players, or over a thousand dollars for a power cable.[4] [5]
• Vendors of audiophile products regularly make fanciful and frankly unscientific claims for the results produced. At one point a company called Tice Audio sold what appeared to be an ordinary clock radio which, it was claimed, would improve the quality of a playback system if plugged into the same electrical circuit, by causing some mystical change in "electron energy".
  Vendors such as Shun Mook market a variety of disks and clamps which, when attached to audio components, are claimed to improve sonic performance.
• In particular, vendors of audio cables have been prone to claims, and to pricing, which strain credulity. There have been audio cables which are filled with water, which glow in the dark, and which come with a separate AC cord which must be plugged in to power the workings of the cable. Those versed in the physics of electrical conductivity often find the prices paid for cables to be laughably high, and at best consider them a form of jewelry.
• Some audiophile claims, while superficially based on accepted physical principles, apply them to circumstances where they are not relevant; for instance the skin effect which relates the efficiency of cables to the frequency transmitted is often referenced with regard to audio frequencies, where it is not significant.
• Many (not all) of the most outspoken audiophile insiders, including reviewers, columnists and pundits lack engineering training and objective credentials. This gives rise to a credibility problem and most will fully admit a lack of understanding as to the technical merits of what they are analyzing, but nevertheless praise a product's innovation and performance. (does this remind you of someone?)

Overall the audiophile world is looked upon by skeptics as being a hotbed of gullibility and fraud, its marketing engine driven primarily by either a constant desire for oneupsmanship or a more benign desire to tinker with equipment; in particular, the tinkering drive is fed by wild claims for minor parts of the system such as cables. In turn, skeptics are often harshly dismissed by dedicated audiophiles as "meter men", people who simply refuse to recognize what the audiophiles consider obvious. The debate is rather heated in certain quarters, and even James Randi chimed in on the issue in 2005.

Edited by MikeEnRegalia

>>he, he well played Goose!

And sorry for the big pic

Denon CDr 1000 The best of market:



Yes the difference between the Pionner and the Denon is real.
Like said "What hifi" in the article up, each digital (recording) device adds it own sounds, and due to the components, alimentations, etc...make the sound aesthetic of the device and its performances of course.
So when you copy an original on such a burner, YOU DON'T DEGRADE THE PERFORMANCES like with a computer copy, or simply a high-speed copy on the good burner (but which is still better than a computer copy, which is the worst)but of course the device gives his own sound, even if its very subbtle and only perceptible on a transparent system and not a computer of course.

For the moment, the Denon is the best burner of the market, its already a few years old, but still the best.

Ther's no the smallest harshness on these good copies, no loss of dynamic, image, low, high, and the more obvious 3is the highs wich are perfectly smooth while on the computer-burned, its harsh, breaks ears &nd ruins evrything.
I would not tell that if i were not sure.
I gave a whole collection of 150 CD (mainly prog)to a non-audiophile friend...i can't stand it anymore and always get original or make good copies on my burner from a new original.
I also avoid occasion CDs cause ther's always the risk of micro-scratchs which makes the correction circuits work more...and it brings harshness, i've made the test.

All these comparisons give obvious resulst on my system; you just to hear a few seconds each CD to hear the diffrence.
Of course, i've got a big system which allows me to hear the difference. On a computer, ther's absolutely not the smallest difference...so, everything is relative.

For your information, Mike, knows that the worst of all is the CD done from a MP3 file (of course the higher the compression, the harsher the sound)or other compressed media, i'm not an expert in these kind of things!
The MP3 and others is the worst thing ever created to reproduce sound.
Cd was the poorest source, now mp3 is worst and SACD and DVD-A are still under the CD...

On another hand, in the video field, the "Blue ray disc will be better" than the DVD for image, thanks to his high storage capacity.

oliverstoned wrote: MikeEnRegalia wrote: oliverstoned wrote: Another point: i've noticed on my audiophile burnerthan 2X speed degrades much, compare to normal speed... Then your burner sucks. BTW: There's no such thing as a audiophile burner. Either the burned CD is a perfect copy, or it isn't. (Read my file -> CD -> file post on the previous page). One more time, theories don't match with reality. My burner (pioner) makes PERFECT copies in normal speed 1X. Btw, here's the best of the world (Denon CDR1000)

goose wrote: oliverstoned wrote: ..and i verify by myself another point is that some kind of blank cds sound different than others, thanks to the chemical product used for the reflective part of the CD. How do you explain that? You argue that analogue is better than digital because digital is just 1s and 0s. If digital is just 1s and 0s, then the chemical has no bearing. If the chemical used alters the sound, there must therefore be more to digital recordings than just 1s and 0s, and so why is analogue better?

Could you please reformulate?

Another point: i've noticed on my audiophile burnerthan 2X speed degrades much, compare to normal speed...

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Not all CDRs are created equalBy Ron Kubara, Business Development Manager, Noritsu Canada Ltd.Ron KubaraImage permanence for CDRs (Compact Disc Recordable) is an area that is not well known or understood by thegeneral consumer, nor by many photo labs. Contrary to popular belief, most CDRs are not permanent, and low-priced CDRs may not be readable at all and error in as little as two years.A cheap CDR is great for moving files fromone PC to another, but risky if being used toarchive files or images. Quality CDRs utilizehigh-quality recording and reflective layers,and are well sealed to reduce the harmfuleffects of the human environment.The material used for the plastic substrate (polycarbonate) of the CD and CDR is also important, as it needs to begas impermeable. Unfortunately, no plastic is; but some plastics are better than others. Even more important is thequality and thickness of the top coatings used to seal layers coated on the substrate.Prerecorded CDs are made by “stamping” the information into the plastic substrate, then analuminum alloy coating is applied to the “bumpy” stamped surface. The laser either reflects offthis reflective layer and a “1 bit” is determined, or the laser is deflected by the “stamped” bumpand a “0 bit” is determined. Contrary to popular belief, the recorded layer of a CD/CDR is not“sandwiched” within the plastic substrate. A clear lacquer protective layer is put on top of thealuminum reflective layer. A label is put on top, or a thick ink coating is applied. As the CD isread from the plastic side, a paper, plastic or ink label applied to the CD provides extraprotection against the data surfaces being scratched.CDRs are not stamped with the data; they are burned with data by the end user. The plastic polycarbonate,however, is stamped with splines (tracks or lines) for the laser to follow. A recording layer is also referred to as thedye layer, and it is sprayed on top of these splines. Four basic chemical formulae are used for the recording layerdye:1.Cyanine/light green/blue in color: low cost to make, most common and lowest permanence.2.Phthalocyanine/transparent with a slight green tint: highest permanence and second most common.3.Metallized Azo/blue: similar in quality to Phthalocyanine, costs less to make and are not common.4. Formazan/light green: combination of Cyanine and Phthalocyanine, similar in quality to Phthalocyanine, costsless to make, and are not as common.CDR manufacturers may modify one of these dyes and create a custom, proprietary formula and/or change thetraditional color of the dye. Thus, CDR color cannot accurately be used to determine the type of dye used.CD read lasers are infrared and are not affected by the color or visible light opacity of the dye. As a result, therecording layer dye color is irrelevant to the laser, as it will effortlessly pass through any dye that is not infraredopaque. The dye will become infrared opaque when burned by the write laser.“Funky” CDRs have a colored dye layer in front of the recording layer dye, creating colored CDRs. Black CDRsblock visible light from reaching the recording and reflective layer; thus, these layers cannot be seen by the eye.Yet, the type of black dye used will let the infrared laser pass.Gamers and music experts believe black CDRs produce better quality CDRs, but this researcher could not find anyscientific evidence to support this claim. As a black layer prevents visible light from reaching the recording layer dye(these dyes will fade over time when exposed to visible light), a black layer may increase longevity over an identicalgrade CDR when both are stored in the light.
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A reflective coating made of silver alloy, pure silver, or pure gold is layered on top of the recording layer. Althoughsilver will show the true color of the recording layer dye, gold will change the dye color because of its yellowishcolor. The burning laser melts a “pit” into the dye, which then blocks the read laser from reflecting back, and a “0bit” is determined. A good dye burns a nice clean pit, so the read laser knows for sure if it is a “0 bit” or “1 bit.” If theburn is not clean and the edge is not a clean cut, the CDR will produce an error.To protect the coatings, lacquer is applied, and high-quality manufacturers make it nice and thick or will even applya separate protective coating. Poor CDRs have very little protection on the coatings and will scratch easily, orworse, delaminate. By writing with a nonwater-base felt pen, the ink could make its way to the data layer anddamage a poorly sealed CDR. But be aware that even the best-coated CDRs can be damaged over time bynonwater-based felt markers.It is difficult to use CDR color only as a guide; but as a general guideline, if the CDR does not have a color tint, it islikely a lower-quality silver alloy with a poor dye layer. Blue, green, and faint green CDRs will be good if they usedquality silver. Unfortunately, there is no way to know for sure. Gold CDRs are the best because, when themanufacturers use gold, they use a quality dye. But don’t be fooled by manufacturers that place a gold-color labelon the non-read side, or the ones that add a funky gold-color layer on the read side.There are several reasons for good or poor CDR permanence.1. Plastic (polycarbonate substrate) is oxygen permeable. Oxygen eventually makes its way through the non-lacquered side (as well as the lacquered side in some cases) and reaches the reflective layer. As aluminumcorrodes when exposed to oxygen, and silver corrodes or tarnishes when exposed to sulfides in air, airreaching the reflective layers will cause corrosion, causing a read error. This could happen in as little as twoyears with poor CDs. Gold CDRs are best in this area, followed by gold/silver alloy. Silver/aluminum alloy is thepoorest.Equally important is the optical quality of the plastic. High optical-quality CDRs permit the light to pass throughthe polycarbonate with little or no diffusion, permitting a cleaner burn to the dye. The spiral grooves stamped tothe CDR vary by manufacturer. It is easier and cheaper to make a V-shaped groove than a sharp edge Ugroove. A V-type stamp will have a higher degree of skipping errors, as the laser may not be able to trackproperly, much like the needle of a phonograph if it does not have enough weight on it. Additionally, the stampwill wear as it stamps CDR after CDR, resulting in a U-shaped groove becoming more V-shaped over time,which may lead to skipping and errors.2. The dyes used in the recording layer are light sensitive, and will react to ambient light and fade over time.Quality CDRs use a dye that resists fading. To be safe, store them in the dark.3. Humidity may seep through a poor lacquer coating. Quality CDRs are well sealed and resist seepage frommarkers and moisture. To make them last, store in low humidity, and use water-based markers and write on thecenter core.4. A scratch on the base side can be repaired, but a scratch on the lacquer side makes the CD a coffee tablecoaster. Quality CDRs have a thick, protective coating to resist scratches.Archiving reports vary by manufacturer, but 70 years would be low for a quality CDR, with the norm being 100years. Some manufacturers of gold CDRs claim 100 to 200 years. You generally get what you pay for. Don’t putthose precious images on a CDR that costs just a few nickels and dimes.The opinions expressed in this column are not necessarily those of Photo Marketing magazine or Photo MarketingAssociation International.

cobb wrote: I'm sure oliverS is just doing this to wind you up Mike. What's he saying now- that the digital information on any two cd's (that contain the same information) from different manufacturing processes can produce different results. Huh? Any two cd's holding the same original information can only be identical in the binary code they represent.

Thanks cobb ... I'm not willing to give up yet.

BTW: I think he's talking about different CD-R media types, not pressed CDs. But of course what you (and I) said applies to them as well.

Edited by MikeEnRegalia

oliverstoned wrote: Yes i know what placebo is. It's like when someone wants to believe that what he has studied in a book fits with the facts.

I have proven my theory to be true, so it cannot be a placebo. Facts don't lie. I have said repeatedly that much of what you say is true, but the chemical substance of a CD doesn't affect the sound.

Let's approach this from another direction. When a CD is manufactured, what essentially happens is that a 650 MB file is transfered to a big machine which somehow prints that file onto a CD.

Now let us suppose that I can read that file from such a CD so that it matches the file which was sent to the CD pressing "machine" (I'm referring to that as a black box, I know it is more complex). Bit for bit identical.

If that is so, how can the material of the disc affect the sound? The material, the mechanics, the moon phase ... neither of that can retrieve more information from the disc than what was in the file which was used to create it.