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CDs And Green Markers. Please Don’t Laugh.

I’m sorry. I apologize. If anything has been done to death, it’s this. And yet . . . 

I was pulling “Darkness On The Edge Of Town” out of my CD player the other day and wondering if Bruce had really made peace with his father when I noticed the edge of the disc was green. Looking through my collection, I found a bunch of them so marked. “Let It Be” by The Replacements. “Murmur.” Stuff that came out during the brief period after the introduction of the CD and before the green pen became an embarrassment. 

I should give a quick kudos to the albums that have survived countless culling that keeps my active collection at about 500 discs. Discs that are easily stored because I always take the discs and printed media out of the ridiculous plastic “jewel” cases and put them in DiscSox, an invention I can’t believe has been overlooked by the Nobel committee. 500 discs fits into five trays from Office Depot and the whole collection takes up about 16x30 inches and the height of a CD. I can’t imagine living with the original packaging. 

I never A/B’ed any of the albums with the green marking. Never looked into the science of the green pen. Back in the day, it was cheap, it was easy, and it was supposed to work. Why not try it? When it became a laughingstock, I stopped. 

But like skinny ties, I assume that green markers have come in and out of vogue many times since 1982. I love a good tweak and wonder if anyone has justified the use of the green marker. I’m not looking far a scientific explanation. Herbie’s Super Black Hole actually works but without anything close to a reason for doing so. I’d be thrilled if the same was true if green pens. 

Besides, those looking for science in audio forums should familiarize themselves with a priori reasoning, and the problems attendant upon it. 

Where have I gone? Why so much wandering? Is it because the initial question is so stupid? Still, I’d like to know: Has anything happened since, say, 1985, that would make greening the edge of CDs sensible?

If not, I promise to apologize and slink quietly back into the darkness.

paul6001
tweak1
3,667 posts
 

I remember the green marker days, as previously mentioned, I have the German Edge cutter machine, which is gathering dust (make me a reasonable offer) Machina Dynamica has been in the taming scattered laser light game for decades. His latest and GREATEST product is called NEW DARK MATTER. It looks like Mica, is applied to the tray under the CD and absorbs/neutralizes all? scattered laser light inside the mechanism, which is the reason for greening.

Don’t think twice: do it

denverfred's avatar
denverfred
252 posts
 

At the risk of being charged with incitement, I humbly ask if anyone has tried the new ceramic or graphine car treatments on a CD.

I have some here and promise I will report back ONLY if I hear some difference.

Problem is: which CD do I care the least about if something negative occurs.

 

mapman's avatar
mapman
22,303 posts
 

Since the system is based on reflected light detected by a sensor, its certainly possible that mucking with the color of the disc could produce some effect. Does ot actually do that? Don’t know. For example, green light is in the middle of the part of the EM spectrum that human eyes can see. Assuming the sensor in the player detects visible light similarly to a human eye, which is just an assumption for argument purpose…don’t know the tech details of the light sensor in a CD player, If you see green now where it was essentially white prior, that means red and blue light is absorbed and that change might produce different results.

 

Might….

 

Should be easy to verify if so by someone with proper technical knowledge of how CD players are designed. No leap of faith should be required.

In general blue or higher frequency light scatters more (hence the sky is blue) so anything that reduces relative levels of blue light should probably be better. That’s just my assessment. Maybe someone with more technical knowledge of CD optical drive design can speak to it better.

I would only add that I would expect a good CD player design to already take the facts into account in the design and not rely on external tweaks for optimal performance. But you never know. Designs are not necessarily created equal. If it’s a cheap tweak that makes up for some design flaw, so be it.

 

What would surprise me is if the tweak made a big difference with a truly high quality CD player. Much less likely I would assert.  

 

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