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[i]Laserdisc[/i] Stop Light?

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Have anyone here ever put the green marker stuff on their CDs/DVDs called "Cd Stop Light"?

I've found it to greatly improve the quality of CDs, especially on my dad's stereo.

Would you say this would be a wise thing to do with laserdiscs as well?

I'm a bit leery about it.

My stance on revising fan edits.

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I've always thought this was a myth/urban legend thing.
“Voice or no voice, the people can always be brought to the bidding of the leaders. That is easy. All you have to do is tell them they are being attacked and denounce the pacifists for lack of patriotism and exposing the country to danger. It works the same in any country.” — Nazi Reich Marshal Hermann Goering
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You can clearly notice any differences? I mean, it's digital, so it either plays with the best sound quality it can offer, or it dosen't.
“Voice or no voice, the people can always be brought to the bidding of the leaders. That is easy. All you have to do is tell them they are being attacked and denounce the pacifists for lack of patriotism and exposing the country to danger. It works the same in any country.” — Nazi Reich Marshal Hermann Goering
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The thing with these markers is, when a cd player has trouble reading the data stream on a cd, there's no time to go back and re-read what it missed like EAC does. This is real-time, the song has to keep going, so most cd players just do the best they can. If they miss some info, so what. Interpret what you've got and move on. So the markers are supposed to I guess make the discs more reflective, or somehow make it easier for the cd player to read what's on the disc. That way more of what you hear is what was actually recorded on the disc, instead of the cd player's best guess at what was on the cd.

I've never really tried them. I have no idea whether they make any real difference at all. If the above explanation is correct, I would imagine that if they do work at all it would be with lower quality cd players that seem to have a real problem reading lots of discs.

Also no idea what they would do to a laserdisc. Again I would imagine a more across-the-board benefit would be seen by buying a better laserdisc player instead of a magic marker.
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Hi,
I am a keen audio enthusiast and also have soem hi end audio equipment and elite laserdisk player.

I know the exact item in question.
I have tried the Green pen technique and it does work but dependent on your system and observation.

To an enthusiast there is change in the sound and some in the picture.
To a person not used to modding i would say that they wouldnt realise much change.

I have tried many mods to both Ld and Cd players.

I had some cds frozen and they sounded very good.

One good mod is to use blue tack underneath the LD player so it is stable on a platform etc.
Just 4 blobs of blue tack on the feet can make a huge difference.

In theory the green pen should refract any red laser thats bouncing of the cd surface as the laser hits it.
Red being opposite on the colour wheel to green,or so the theory goes.
Laserdisk players also make great cd transports as the mechanisms are overly engineered for smaller disks.

Also removing the transformer out of most hi fi and externally using it will improve matters.

Thanks,
Ian(uk).
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It makes no sense, as the sound on a CD is digital information. If the laser can't read it, then it uses some bit correction algorithm such as CRC to "guess" what was missing. If it still can't read, it "skips" that part. A CD will never sound "better" or "worse" depending on "laser reflexion", it either sounds the better possible, or it dosen't play at all.
“Voice or no voice, the people can always be brought to the bidding of the leaders. That is easy. All you have to do is tell them they are being attacked and denounce the pacifists for lack of patriotism and exposing the country to danger. It works the same in any country.” — Nazi Reich Marshal Hermann Goering
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Maybe not on your sound system, but it sure does on mine.

See, my dad has modified this stereo setup since he got out of high school.
His life work is in this stereo.

I could tell a difference there.




So I tried just doing on my old crappy CD player, and it sounded the same.

So it depends on your setup.

My stance on revising fan edits.

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Out of curiosity, how did your dad modify a CD Player to care about the green marker issue?
Schnapple
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Not mainly the CD player, but the stereo.

We've gone through several CD players. The excellent one we use it the size of my laserdisc player almost.



I couldn't even begin to describe what he's done with his stereo. It's wonderful.

My stance on revising fan edits.

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HI,

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"It makes no sense, as the sound on a CD is digital information. If the laser can't read it, then it uses some bit correction algorithm such as CRC to "guess" what was missing. If it still can't read, it "skips" that part. A CD will never sound "better" or "worse" depending on "laser reflexion", it either sounds the better possible, or it dosen't play at all. "

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Yes the sound of a cd is in the digital domain but when the laser is hitting the surface there is relection and the error correction cuircuitry plays its part.
By lowering this you make the player have a much easier time and error correction etc is therefore not needed and laser direction is much more exact and not prone to wow and flutter.
It all depends on your system and tastes in hi fi.
There are so many factors that can be applied to modding cd players the main ones being in the power supply,Output cappacitors,Copper shielding,Vibration control and unteen other things.

I did hear a difference on my system.
Thanks,
Ian.
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Oh well whatever.
“Voice or no voice, the people can always be brought to the bidding of the leaders. That is easy. All you have to do is tell them they are being attacked and denounce the pacifists for lack of patriotism and exposing the country to danger. It works the same in any country.” — Nazi Reich Marshal Hermann Goering
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Hi everyone!

Well my first post on this forum and it's not even to do with Star Wars - hahaha!!!

There's no such thing as wow and flutter with CD!! Records and tapes yes - CD definately no! The information is all read into a buffer anyway before it is converted to analogue and then to the amp/speakers. There is something called 'jitter' which affects CD's, though it doesn't seem to be a very well understood or correctable problem.

This whole green pen business is also rubbish! It's interesting that audio engineers are agreed it makes no difference whatsoever, and those who only rely on the ears think it does! There was a forum where someone had actually run some error correction tests on CD's (wish I could find it again) with and without the green pen treatment - there was zero difference. If your cd player or laserdisc player needs a green ring drawn around the disc to play it properly, then the player is a bad design! I've got a very good quality Hi-Fi system, and I've tried this green pen treatment many times - blindfolded I cannot tell the difference! The human brain is a cunning piece of work, and can fool you into thinking you've heard a difference because you've been told, or read somewhere that you 'should' hear a difference.

The one treatment that does make a measurable difference is the thorough cleaning of your CD's or LD's. A good quality plastics cleaner should be used with a VERY soft lint free cloth. Make sure the laser in your CD player or LD player is perfectly clean as well, and the player sits on a stable platform away from any vibration.

Just my 2$ worth (or in my case my £2 worth!!!)

Happy listening/viewing!

- John