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Audio absurdities
pdq
post Mar 30 2011, 13:46
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QUOTE (thesurfingalien @ Mar 30 2011, 07:54) *
However, given that the receiving end is completely unaware of when the actual signal started, and that the time it takes for a signal to get from sender to receiver is of no influence on the order or the length of the sent pulses (in a digital situation), I can not see any reason why the speed as a property be responsible for eliminating jitter.

If different frequencies travel at different speeds (dispersion) then over a great enough distance the shape of the pulse can change, making it more difficult to detect the exact time of a pulse edge. That could theoretically increase jitter.

All of this is orders of magnitude below what is actually significant.
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thesurfingalien
post Mar 30 2011, 14:29
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This is hear-say, and I have some serious doubts if the actual event really took place...

However, the fact is that at some point a story hit the audio community that CD's sounded better when they were cold, even frozen.

I heard a story from a friend (who had a friend etc...) that someone visited with someone who had a big freezer in his listening room where he stored his CD's at minus 24 degrees Celsius (=minus 11.2 Fahrenheit). His reasoning? "I have a rather "warm" sounding amplifier, and "cool" CD's correct that."

Besides that fact that a CD probably needs about a minute or two to get to room temperature again, I believe that cold "things" actually attract moisture when brought into a warmer environment. That is probably not beneficial to a CD player at all...
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thesurfingalien
post Mar 30 2011, 14:56
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QUOTE (pdq @ Mar 30 2011, 09:46) *
If different frequencies travel at different speeds (dispersion) then over a great enough distance the shape of the pulse can change, making it more difficult to detect the exact time of a pulse edge. That could theoretically increase jitter.

All of this is orders of magnitude below what is actually significant.


I believe that to be an incorrect assumption as the time of the pulse will remain the same. Only the beginning and ending of the pulse will be received earlier in time; in between nothing changes.

Regards,
Peter


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pdq
post Mar 30 2011, 15:33
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QUOTE (thesurfingalien @ Mar 30 2011, 09:56) *
I believe that to be an incorrect assumption as the time of the pulse will remain the same. Only the beginning and ending of the pulse will be received earlier in time; in between nothing changes.

A pulse is not a single frequency. If you don't believe me, create a square wave in an audio editor, then low-pass it. You will find that the shape is now greatly distorted. You will see the same effect if you apply a frequency-dependent phase shift.
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thesurfingalien
post Mar 30 2011, 16:00
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QUOTE (pdq @ Mar 30 2011, 11:33) *
A pulse is not a single frequency. If you don't believe me, create a square wave in an audio editor, then low-pass it. You will find that the shape is now greatly distorted. You will see the same effect if you apply a frequency-dependent phase shift.


Sorry, I did not get the context correctly and I believe you. I am just having trouble relating this to the cable-speed scenario. Can you explain this more detailed?

I agree that the effect is minimal up to a point where discussing it is rather pointless, but a day you do not learn something new is a lost day...
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pdq
post Mar 30 2011, 16:20
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I hope this won't be considered too far off-topic if I expand on this...

Probably the most important situation involving dispersion these days is fiber-optic communications. An optical fiber consists of a long, thin strand of a transparent material (usually fused silica) encased in a coating of a material with a different refractive index. Light entering one end of the fiber travels almost unattenuated to the other end. Its speed is the speed of light in the fiber's material.

The light being used to transmit the information is almost monochromatic, but not quite. The refractive index of the fiber is almost constant over the wavelength range of the light source, but not quite. The combination of the bandwidth of the light source and the dispersion (variation of refractive index with wavelength) results in a broadening of a pulse being transmitted, and the leading and trailing edges of the pulse become less sharp.

All of this limits the combination of data rate and fiber length. The longer the fiber, the lower the maximum data rate, etc. Over the years great strides were made in the technology so that we can now send data at hign rates over hundreds of kilometers before needing to amplify and retransmit the signal.

These effects are miniscule when sending audio data over even hundreds of meters of coaxial cable. Even optical transmission of audio data, with relatively high dispersion plastic fibers and LED light sources, is not affected significantly over distances of tens of meters.
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WonderSlug
post Mar 30 2011, 16:50
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QUOTE (thesurfingalien @ Mar 30 2011, 05:36) *
I can not remember when, but at some time one could buy a black CD marker that one should apply to the outer edge of a CD, coloring it black, claiming improvement on sound. I can not recall the specifics, but it had something to do with canceling reflections.

I believe it was an audiophile magazine that analyzed the markers, and found out they were nothing more than regular permanent markers (the Edding brand if I recall correctly), sold at about 25 times the price of the original.


Interestingly, the same method (black magic marker on the outer edge) was applied to certain commercial audio CDs, namely those published by Sony's music group last decade. The reasons were different than cancelling reflections.

Sony stopped making those "special" CDs due to public outcry and some technical issues that arose.
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Roseval
post Mar 30 2011, 16:55
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The Blackbody is a high-tech audio accessory which greatly enhances your audio playback experience by addressing the interaction of your audio gear's circuitry with ambient electromagnetic phenomena and modifying this interplay. The Blackbody takes advantage of the quantum nature of particle interaction, and is therefore able to permeate metal, plastic, wood, and other barriers to affect the circuitry inside your components. This altered electromagnetic influence results in profoundly improved sound quality.


A steal at $ 959 only!
http://www.lessloss.com/blackbody-p-200.html


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pdq
post Mar 30 2011, 17:01
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Years ago a friend of mine was working at Radio Shack. He once told me that he told a customer that he could not use twinlead to connect his speakers because the twinlead was 300 ohms and the speakers were 8 ohms. laugh.gif
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thesurfingalien
post Mar 30 2011, 17:05
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@pdg:

That is a very clear explanation... Thanks!

About too far off-topic... For me it's not a problem at all :-) Hope forum moderators agree too :-)

Thanks again!

Regards,
Peter
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thesurfingalien
post Mar 30 2011, 17:08
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QUOTE (pdq @ Mar 30 2011, 13:01) *
Years ago a friend of mine was working at Radio Shack. He once told me that he told a customer that he could not use twinlead to connect his speakers because the twinlead was 300 ohms and the speakers were 8 ohms. laugh.gif


Was your friend in error, or did he "make fun" of the customer?
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pdq
post Mar 30 2011, 17:31
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QUOTE (thesurfingalien @ Mar 30 2011, 12:08) *
QUOTE (pdq @ Mar 30 2011, 13:01) *
Years ago a friend of mine was working at Radio Shack. He once told me that he told a customer that he could not use twinlead to connect his speakers because the twinlead was 300 ohms and the speakers were 8 ohms. laugh.gif


Was your friend in error, or did he "make fun" of the customer?

He just didn't know any better.
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thesurfingalien
post Mar 30 2011, 18:14
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In Holland there is a pretty "famous" loudspeaker-builder that has some pretty weird "experiments" to prove the quality of his product. He puts a coin on the top of the loudspeaker, and turns up the volume. The fact that the coin does not fall off is proof of quality (no cabinet resonance).

At the time I went there I was greeted by him while he was listening to some vocal music. He moved from the couch, and invited me to sit down and listen to his "best loudspeaker in the world". It sort of puzzles me why he did not hear that the left loudspeaker was connected out-of-phase. After notifying him of that, he corrected it, and I was allowed to play one of my CD's. I noticed that he had also confused the left and right channel.

Besides the fact that he at any given moment stopped my music and played some of his own (that was, according to him, of obviously better quality for testing a loudspeaker of this greatness) he, while discussing his competitors, referred to them as "fumblers in the margin" at best.

His loudspeakers are definitely not the best in the world, and I did not care at all for his disrespectful opinions on his competitors...
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PoisonDan
post Mar 30 2011, 20:41
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This is a nice site, collecting all kinds of audiophile madness:
http://www.ilikejam.org/blog/audio/audiophile.html

This post has been edited by greynol: Mar 30 2011, 21:04
Reason for edit: merged posts


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ron mexico
post Mar 30 2011, 23:25
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QUOTE (Roseval @ Mar 30 2011, 16:55) *
QUOTE
The Blackbody is a high-tech audio accessory which greatly enhances your audio playback experience by addressing the interaction of your audio gear's circuitry with ambient electromagnetic phenomena and modifying this interplay. The Blackbody takes advantage of the quantum nature of particle interaction, and is therefore able to permeate metal, plastic, wood, and other barriers to affect the circuitry inside your components. This altered electromagnetic influence results in profoundly improved sound quality.


A steal at $ 959 only!
http://www.lessloss.com/blackbody-p-200.html



I spent a few minutes looking at the lessloss site - oh my! $4686 for a "power conditioner", of course to be used with 2 "Dynamic Power Filtering" cables which can be yours for the low low price of $1149 each. For maximum benefit one should have a separate power conditioner for each component. Of course the cost is justified by the use of "tankwood". I guess I should not be surprised but sometimes you see something that just takes your breath away.
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DVDdoug
post Mar 31 2011, 00:25
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"Audio Absurdities" would be a great title for a monthly column in an audio magazine! ...If only there were a skeptical-scientific audio magazine. And of course, they might offend potential advertisers.
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Speedskater
post Mar 31 2011, 15:30
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"The Audio Critic" magazine when it was still in print form often had columns similar to your "Audio Absurdities" like the semi-regular "Hip Boots". Unfortunately the last printed issue was in the Summer of 2003. Now we only see an occasional web article. But then Peter Aczel is in his mid-eightieths.

http://www.theaudiocritic.com/cwo/Back_Issues/

This post has been edited by Speedskater: Mar 31 2011, 15:30


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BearcatSandor
post Mar 31 2011, 17:21
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Um.... magic dots which can be covered by white paper. I had a friend who used to use 'magic dots on white paper' adn everything looked and sounded better to him too. I wonder if these are related.

http://www.machinadynamica.com/machina47.htm

(found this following links from Greynol's post above)


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Speedskater
post Mar 31 2011, 17:45
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I was just reminded of this one on another forum:

http://www.lessloss.com/blackbody-p-200.html

It's been around for a while, so it's not an April Fool's joke.


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antz
post Apr 5 2011, 14:27
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Please close this thread before I die laughing. I haven't laughed so much since last time I peeked at the machinadynamica site some time ago, I see they have some new "products" now too. I'd really like to think they're spoof sites and they have no customers, otherwise they just reinforce two sayings: "there's one born every minute" and "a fool and his money...".

What's this obsession with "quantum" whatever being involved? Actually the quantum teleportation upgrade from machina surely takes the biscuit for gullibility?
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andy o
post Apr 5 2011, 17:56
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"Quantum" is one of the words up there with the likes of classics like "energy", "ions", "waves", etc. which are clearly defined terms that nevertheless pseudoscientists use out of context, out of their actual meaning and use them to confuse, sound "sciency" and pretend that they know what they're talking about.

Example: http://www.youtube.com/watch?v=-y5D7q1O1Uk

That was right after Chopra bastardized terms like "locality", "entanglement" and of course "quantum". He's one of the most egregious offenders btw. It's not just audio. It's everywhere.
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flaminio
post Apr 5 2011, 20:27
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No thread of this sort would be complete without the Denon AKDL1 Dedicated Link Cable.

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BearcatSandor
post Apr 5 2011, 21:12
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That's not quite a Cat-5 is it? If you look through the submitted pictures on the amazon link, someone make a Portal gun using them. Cool.

The customer reviews on that cable on Amazon are hilarious.

This post has been edited by BearcatSandor: Apr 5 2011, 21:14


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thesurfingalien
post Apr 5 2011, 22:09
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QUOTE (antz @ Apr 5 2011, 10:27) *
Please close this thread before I die laughing. I haven't laughed so much since last time I peeked at the machinadynamica site some time ago, I see they have some new "products" now too. I'd really like to think they're spoof sites and they have no customers, otherwise they just reinforce two sayings: "there's one born every minute" and "a fool and his money...".

What's this obsession with "quantum" whatever being involved? Actually the quantum teleportation upgrade from machina surely takes the biscuit for gullibility?


I have friends that are (or once were) heavily involved in the "paranormal" world. The same thing happens there, but usually at a lower price-level. There are companies out there that prey on gullible people, and make big money that way. I think it pretty much started with people that have an interest in paranormal stuff, and they turned out to be easy victims. Just through in a few "educated-sounding" terms, some pretty outrageous explanations that no-one can either prove or disprove and add some completely meaningless, irrelevant or nonexistent titles. Mix that and you have a good recipe for things that sell in that community.

Now I believe the same companies have found (some time ago already) a new market... Maybe the level of gullibility is lower, but we are talking about people that ARE WILLING TO SPEND BIG BUCKS on improvements. And, again, it works! People buy into that kind of mambo-jumbo and spend their hard-earned money on nothing short of utterly BS products, recommended to them by "knowledgeable" people.

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Porcus
post Apr 5 2011, 22:11
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QUOTE (probedb @ Mar 30 2011, 13:44) *
QUOTE (Andavari @ Mar 30 2011, 13:10) *
CD rings/guards which were thin round rings either rubber or flexible plastic that went on the outside edge of a CD (personally I'd just call them CD rubbers) were in some audio-type magazines back in the 1990s.

They were marketed as "protecting and stabilizing to increase audio quality" for audio CDs during playback since they supposedly raised CDs an insignificant amount off the CD tray. But in reality they caused more problems, could get slightly baked onto the CD leaving residue behind on the outer ring of the disc, and if they broke off whilst inside a CD player it could become damaged.


That's quite amusing considering the CDs don't sit on the tray during playback anyways wink.gif


On some Pioneer models, it would. The disc would be upside-down on a turning platter, meaning that you could not use those plastic disc clamps.

I actually heard a «disc clamp» kind of thing that made an audible difference. I mean, a «WTF?» level of difference. Never had the chance to check out the details, but I suspect there was some resonance rattling off in the player itself. (Hm ... if I had such a CD ring, I'd try the trick on my early DVD-player ...)



QUOTE (thesurfingalien @ Mar 30 2011, 13:36) *
I can not remember when, but at some time one could buy a black CD marker that one should apply to the outer edge of a CD, coloring it black, claiming improvement on sound. I can not recall the specifics, but it had something to do with canceling reflections.

I believe it was an audiophile magazine that analyzed the markers, and found out they were nothing more than regular permanent markers (the Edding brand if I recall correctly), sold at about 25 times the price of the original.


Obvious fraud. The ones that did deliver the sonic bliss, were the green ones. cool.gif


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