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Painting the edge of a CD green


mansr
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Some say painting the edge of a CD green makes a difference to the playback, specifically that it affects the jitter. I decided to test this myself. To this end, I burned a J-test track to a CD-R and recorded the playback. Then I painted the edge green and recorded it again. Below is the spectrum of this:

 

green-cd.png

 

The blue trace is before painting the edge, the green one after (obviously). While there is clearly some jitter present here, there is no change whatsoever to be seen. There are some very minor variations in the four small peaks not part of the jitter pattern. However, these vary slightly from run to run regardless, so the changes cannot be attributed to the green edge.

 

I can't say I'm surprised.

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Some say painting the edge of a CD green makes a difference to the playback, specifically that it affects the jitter. I decided to test this myself. To this end, I burned a J-test track to a CD-R and recorded the playback. Then I painted the edge green and recorded it again. Below is the spectrum of this:

 

[ATTACH=CONFIG]25980[/ATTACH]

 

The blue trace is before painting the edge, the green one after (obviously). While there is clearly some jitter present here, there is no change whatsoever to be seen. There are some very minor variations in the four small peaks not part of the jitter pattern. However, these vary slightly from run to run regardless, so the changes cannot be attributed to the green edge.

 

I can't say I'm surprised.

 

There are earlier published results that showed that Jitter is actually increased.

Jud may be able to link to this perhaps ?

 

How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file.

PROFILE UPDATED 13-11-2020

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Did you use the correct green paint?

http://www.amazon.com/AudioPrism-CD-Stoplight/dp/B00OU5C4VY

This is the right stuff. I actually still have one of the correct paint pens from the early days.

 

And what CD drive did you use? That might matter.

 

I have seen the reports showing increased jitter. Working from memory though it was differences smaller than you are showing and blown way out of proportion.

 

Just after the 30 minutes mark in this video if you wish to bother.

 

Also worth a laugh is just after the 39 minute mark talking about cable. He shows a pile of 100 ft of what he uses to record. Says it is medical cable (I recognize it as instrumentation cable used where I worked), and he says it isn't as good as a real high end cable like you have, but I can adjust my gear so it comes out okay. Which of course made me wonder, well why don't we adjust our home gear instead of buying expensive cable for 1 meter? And if this is carrying the original microphone signals and isn't as good as MIT then why the heck would KOJ not go to the expense of some MIT for his microphones? Ponder that a bit.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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A linear power supply needs to be used to mix the green ink. Otherwise it is impossible to conclude anything from these so-called experiments. Three separate people at a bus stop in Kiokuk, Iowa were able to hear clear differences. Hearing is believing.

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Did you use the correct green paint?

http://www.amazon.com/AudioPrism-CD-Stoplight/dp/B00OU5C4VY

This is the right stuff. I actually still have one of the correct paint pens from the early days.

 

And what CD drive did you use? That might matter.

 

I have seen the reports showing increased jitter. Working from memory though it was differences smaller than you are showing and blown way out of proportion.

 

[ATTACH=CONFIG]25981[/ATTACH]

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Did you use the correct green paint?

http://www.amazon.com/AudioPrism-CD-Stoplight/dp/B00OU5C4VY

This is the right stuff. I actually still have one of the correct paint pens from the early days.

 

And what CD drive did you use? That might matter.

 

I have seen the reports showing increased jitter. Working from memory though it was differences smaller than you are showing and blown way out of proportion.

 

I used a random (Faber-Castell brand) green marker I happened to have. There's no way I'm spending $25 on something that almost certainly doesn't work. Besides, I never listen to CDs directly, so I'd have no use for it even if it did. Moreover, the effect was obviously "discovered" before that dedicated pen existed, so it must "work" with at least some generic ones.

 

I used an ancient Sony D-50 CD player. It's the only standalone one I have around, but I can try it with a PS3 or a random CD-ROM drive. I think I still have some with analogue outputs.

 

The ADC was a Tascam UH-7000 modified to use an external power supply.

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For a group of seemingly smart guys, you folks seem to waste a lot of time chasing after some specious and irrelevant bullshit.

Let me be the first to congratulate you (other than yourselves) for your tireless efforts on behalf of the audio community.

You must have chaos within you to give birth to a dancing star

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I used a random (Faber-Castell brand) green marker I happened to have. There's no way I'm spending $25 on something that almost certainly doesn't work. Besides, I never listen to CDs directly, so I'd have no use for it even if it did. Moreover, the effect was obviously "discovered" before that dedicated pen existed, so it must "work" with at least some generic ones.

 

I used an ancient Sony D-50 CD player. It's the only standalone one I have around, but I can try it with a PS3 or a random CD-ROM drive. I think I still have some with analogue outputs.

 

The ADC was a Tascam UH-7000 modified to use an external power supply.

 

Well, see my edited post above for more info.

 

If you used green ink as in felt tip magic marker it really is different. At least get a $6 paint pen from a craft store. The green stuff they sold was actually pretty thick paint, not like a felt tip marker. An acrylic paint pen is the right stuff.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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I have seen the reports showing increased jitter. Working from memory though it was differences smaller than you are showing and blown way out of proportion.

 

Just after the 30 minutes mark in this video if you wish to bother.

 

Of course there's no information on the measurement setup he used. Makes it impossible to replicate the experiment. Perhaps that's why this remains the one and only positive report of a measured effect.

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For a group of seemingly smart guys, you folks seem to waste a lot of time chasing after some specious and irrelevant bullshit.

Let me be the first to congratulate you (other than yourselves) for your tireless efforts on behalf of the audio community.

 

I personally feel like it is a great benefit to the audiophile community. If I was like some people, I would become a purveyor of goods that are crap and market it to them. They would spend large sums of money, and the community would be poorer for it. On the other hand I would be richer. So us amateur BS pursuers are the best of the breed. By remainging amateurs we by default enrichen the community.

 

So we accept graciously your congratulations. Thank you.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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There are earlier published results that showed that Jitter is actually increased.

Jud may be able to link to this perhaps ?

 

I tried it in the 80's, sounded compressed so gave up on that idea.

There is no harm in doubt and skepticism, for it is through these that new discoveries are made. Richard P Feynman

 

http://mqnplayer.blogspot.co.uk/

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For a group of seemingly smart guys, you folks seem to waste a lot of time chasing after some specious and irrelevant bullshit.

Let me be the first to congratulate you (other than yourselves) for your tireless efforts on behalf of the audio community.

 

Maybe I'm just bored.

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For a group of seemingly smart guys, you folks seem to waste a lot of time chasing after some specious and irrelevant bullshit.

Let me be the first to congratulate you (other than yourselves) for your tireless efforts on behalf of the audio community.

 

For a seemingly smart guy, you seem to waste a lot of time complaining about how other people spend their free time.

Sometimes it's like someone took a knife, baby
Edgy and dull and cut a six inch valley
Through the middle of my skull

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What's a CD?

 

Certificate of Deposit. At least that is the CD where the green really makes a difference.

And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. 

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For a group of seemingly smart guys, you folks seem to waste a lot of time chasing after some specious and irrelevant bullshit.

Let me be the first to congratulate you (other than yourselves) for your tireless efforts on behalf of the audio community.

 

Yeah, but this is pleasant compared to the rampage of a priapic raptor.

1070957250_Imprimatur.NihilObstatSepia3Crop(2).jpg.2162a44365e84a5df7d456bf8026ed67.jpg

 

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For a seemingly smart guy, you seem to waste a lot of time complaining about how other people spend their free time.

 

Then again maybe I am not too smart and prefer to spend my increasingly shrinking free time actually learning something important here, as opposed to wading through noise.

 

Carry on.

You must have chaos within you to give birth to a dancing star

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Some say painting the edge of a CD green makes a difference to the playback, specifically that it affects the jitter. I decided to test this myself. To this end, I burned a J-test track to a CD-R and recorded the playback. Then I painted the edge green and recorded it again. Below is the spectrum of this:

 

[ATTACH=CONFIG]25980[/ATTACH]

 

The blue trace is before painting the edge, the green one after (obviously). While there is clearly some jitter present here, there is no change whatsoever to be seen. There are some very minor variations in the four small peaks not part of the jitter pattern. However, these vary slightly from run to run regardless, so the changes cannot be attributed to the green edge.

 

I can't say I'm surprised.

 

When the AudioPrism "green pen" first came out, I bought one and my audiophile buddies and I did extensive listening tests by getting two copies of the same discs and painting one green and leaving the other stock. In many blind tries with lots of different types of music from many labels we found no audible difference between the painted and unpainted discs. One thing we did find out was that certain labels couldn't be painted because the silver coating on the back of the disc wrapped around the edge. Anyway, it did nothing to enhance the sound of any disc we painted, so it quickly went in the dustbin.

George

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Then again maybe I am not too smart and prefer to spend my increasingly shrinking free time actually learning something important here, as opposed to wading through noise.

 

Perhaps you need to pay more attention to the title of the thread and who starts it. :)

 

Looking at this one, for example, it's pretty easy to guess how things will play out. :) :)

Sometimes it's like someone took a knife, baby
Edgy and dull and cut a six inch valley
Through the middle of my skull

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Perhaps you need to pay more attention to the title of the thread and who starts it. :)

 

Looking at this one, for example, it's pretty easy to guess how things will play out. :) :)

 

My apologies. You are absolutely correct.

 

Carry on.

You must have chaos within you to give birth to a dancing star

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Some say painting the edge of a CD green makes a difference to the playback, specifically that it affects the jitter. I decided to test this myself. To this end, I burned a J-test track to a CD-R and recorded the playback. Then I painted the edge green and recorded it again. Below is the spectrum of this:

 

[ATTACH=CONFIG]25980[/ATTACH]

 

The blue trace is before painting the edge, the green one after (obviously). While there is clearly some jitter present here, there is no change whatsoever to be seen. There are some very minor variations in the four small peaks not part of the jitter pattern. However, these vary slightly from run to run regardless, so the changes cannot be attributed to the green edge.

 

I can't say I'm surprised.

 

A couple words about this "tweak", it came out in the days when CD players used IR lasers, there are almost none of those left today, most people are either using a DVD drive which uses a red laser or BluRay which of course uses a blue laser. The color of the beam is important since the explanation was having to do with the absorption of the beam by the green ink. The correct ink was also important since it was about the IR properties not the visible properties.

 

So using generic marker ink would not necessarily work the same, and using a modern player would almost certainly not behave the same as a CD player from the day.

 

So doing a test using generic ink with a modern player has very little to do with whether it WOULD have worked with the correct ink and old style CD player.

 

Of course it is a perfectly viable test of whether generic ink works with a modern player.

 

Note I am not saying it DID work back then, just that generic ink with modern player is not an appropriate test of whether it did.

 

John S.

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A couple words about this "tweak", it came out in the days when CD players used IR lasers, there are almost none of those left today, most people are either using a DVD drive which uses a red laser or BluRay which of course uses a blue laser. The color of the beam is important since the explanation was having to do with the absorption of the beam by the green ink. The correct ink was also important since it was about the IR properties not the visible properties.

 

So using generic marker ink would not necessarily work the same, and using a modern player would almost certainly not behave the same as a CD player from the day.

 

So doing a test using generic ink with a modern player has very little to do with whether it WOULD have worked with the correct ink and old style CD player.

 

Of course it is a perfectly viable test of whether generic ink works with a modern player.

 

Note I am not saying it DID work back then, just that generic ink with modern player is not an appropriate test of whether it did.

 

John S.

I used a CD player from 1982. Is that old enough? Also, even modern players have to use an IR laser for CDs since otherwise the reflections wouldn't cancel properly.

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I would say that it might be possible for the green to make a difference. If you take a regular blank DVD and take a blue magic marker and cover the bottom of DVD with it, you can use it as a blank Blue Ray.

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Brain dump:

 

 

  • Combo CD/DVD/BluRay drives indeed have a dedicated laser for each disc type. The "pits" on the disc are 1/4 of a wavelength deep for the laser used. The light "spot" is somewhat larger than the "pit". When no pit is present, all the light gets reflected at the same time. When a pit is present, the light hitting the "bottom" of the pit (which is actually closer to the laser head) gets reflected first. It mixes with the light reflected from the area around the pit. Since the laser light is coherent, the "pit" light is now 1/2 a wavelength out of phase from the non-pit light and partly cancels it. Less light is picked up by the detector.
  • My first CD player was a D50. Last time I tried it, it still worked. Teardown of one:
    EEVblog #863 - World's First Portable CD Player Teardown - Sony D50 - Page 1
  • Many inks are transparent to infrared, so will be no use on the edge of a CD. You can test this out by colouring a piece of clear plastic and seeing if an infrared remote control will work through it.

"People hear what they see." - Doris Day

The forum would be a much better place if everyone were less convinced of how right they were.

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