Give it up. Unless your lathe is wired with braided CAT5 and the motor windings in silver, it won't work.
Then you need to determine which way to spin the disc, while cutting. (I'd make sure all the table legs, in my listening room, were turned in the same direction, for symmetry.)
And finally, if you accidentally plug the lathe in backwards, you'll make it sound worse.
Actually... one thing I do with all new discs... and have done from day one with no ill effect... is to give them a really good polish with spray on furniture polish. Done for purely practical reasons of keeping the disc clean. And of course it makes the disc pretty anti static, and at a microsopic level may even "fill in" minute invisible marks.
Now some one is bound to say... silicone, that's bad.
Well, the proof is in 25 years or so of owning CD's and they are all still mint
Now some one is bound to say... silicone, that's bad.
Well, the proof is in 25 years or so of owning CD's and they are all still mint
Actually... one thing I do with all new discs... and have done from day one with no ill effect... is to give them a really good polish with spray on furniture polish. Done for purely practical reasons of keeping the disc clean. And of course it makes the disc pretty anti static, and at a microsopic level may even "fill in" minute invisible marks.
Now some one is bound to say... silicone, that's bad.
Well, the proof is in 25 years or so of owning CD's and they are all still mint
I just saved a totally unreadable DVD this morning with some Barnsite (a mixture of <.5u cerium oxide and lanthanum oxide used for optical polishing). Sounds like a product in the making, exotic enough sounding to please the tweaker community. You could package up a slurry in little tubes, huge margins guaranteed.
EDIT - Glen's not around to call me an idiot for not knowing that it is also an auto polish, my bad.
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Lol... you could be on to a winner there Scott
Now (don't laugh)... but when faced with a damaged disc I really really want to record (sorry play, I meant play) from the local libraries I have used this on a cotton bud on a pcb drill at low speed.
It's good, a real abrasive polish specially for removing scratches. --|PLASTICCLEAN|PLASTIC POLISH | CPC
This would make some sense if there were actually 0s and 1s on the cd.
I have been done with cds for a while, so zero interest in improving them but people i know and trust actually swear by the diy equivalents of the above devices.
Indeed, i use Brasso (perfect for polishing plastic)Lol... you could be on to a winner there Scott
Now (don't laugh)... but when faced with a damaged disc I really really want to record (sorry play, I meant play) from the local libraries I have used this on a cotton bud on a pcb drill at low speed.
--|PLASTICCLEAN|PLASTIC POLISH | CPC
Just make sure you polish the disc backwards & forwards from the centre to the exterior, NEVER around the disc! It works a treat as long as the scratch is on the read side of the disc. If it's on top it'll probably have damaged the reflective layer & there is no saving it.Didn't Krell manufacture a player that flooded the transport with green light to do something about so called reflections from the disc edge? I'm not into too much snake oil but apparently some red laser light can be reflected though the disc & be picked up on reflection (oh yeah) & be reflected again & mess up a perfectly good reading.
Not sure i believe it myself, could be the MD10 transport that has this. I can't see into my DT10 to see if it has the same. However i'm sure there are so called "CD pens" out there that are designed to put green pen onto the very outer edge of the CD disc to approximate the same thing.
Weird
An arguably more conservative company - Studer - also used a green LED in the D732. Not sure how much this improved anything but it still sounded disastrous, likely due to the TDA1305 dac and 5532 opamps
I suspect that is more likely illumination so you can see that there is a disc in the player and that it's rotating, hence the 'window' in the front of the drawer too. The ReVox B225 and Studer A725 also lit up the disc, as did all the early Philips-based machines.
YBA also included LEDs (blue) with the declared goal of improving the reading S/N ratio of the laser.
It must be said that adding all sort of green or blue LEDs that make the innards of the CD tray look loke a christmas tree is guaranteed to worsen this S/N ratio. If real the reported 'improvements' are most likely a result of this degradation. (much like many other tweaks we see around)
In theory it is possible to use a controlled amount of noise generated from an external source based on the stochastic resonance principles to reduce the noise. See here: http://en.wikipedia.org/wiki/Stochastic_resonance
Making an analogy with the dither used at recording/playback in digital systems where we kinda know the level of noise and the magnitude of the LSB here we would need some pretty cool tools to measure what is that we want reduce and then to design a control loop that modulates the optical noise of our LEDs accordingly. First obstacle: how to apply it to only one of the beams without hacking inside the optics assembly?
It must be said that adding all sort of green or blue LEDs that make the innards of the CD tray look loke a christmas tree is guaranteed to worsen this S/N ratio. If real the reported 'improvements' are most likely a result of this degradation. (much like many other tweaks we see around)
In theory it is possible to use a controlled amount of noise generated from an external source based on the stochastic resonance principles to reduce the noise. See here: http://en.wikipedia.org/wiki/Stochastic_resonance
Making an analogy with the dither used at recording/playback in digital systems where we kinda know the level of noise and the magnitude of the LSB here we would need some pretty cool tools to measure what is that we want reduce and then to design a control loop that modulates the optical noise of our LEDs accordingly. First obstacle: how to apply it to only one of the beams without hacking inside the optics assembly?
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Even though virtually every die hard subjectivist reviewer has a desert island list of CD's.
It's a ******* storage medium that's all...
got a better one?
...and this one ain't so good because they scrapped the second clear layer of polycarbonate (or whatever plastique they use) that was supposed to cover the silvered layer... thus the life of the CD from an archival point of view is limited by the side with the labels on it...
Btw, since the laser and photodiode arrays work on the infrared range and are just about totally blind to "blue light" I somehow doubt that it would worsen the S/N. Have you ever put an LED or Laser on a spectrometer and looked at the output? Nothing there out of band. Nada, zilch, zip.
_-_-bear
got a better one?
...and this one ain't so good because they scrapped the second clear layer of polycarbonate (or whatever plastique they use) that was supposed to cover the silvered layer... thus the life of the CD from an archival point of view is limited by the side with the labels on it...
Btw, since the laser and photodiode arrays work on the infrared range and are just about totally blind to "blue light" I somehow doubt that it would worsen the S/N. Have you ever put an LED or Laser on a spectrometer and looked at the output? Nothing there out of band. Nada, zilch, zip.
_-_-bear
The signal read off the CD is not 0s & 1s. It is an analog RF signal that tries to represent the 1s & os in the pits of the CD.
Instead of dismissing it with no real discussion, i think it worthwhile to consider mechanisms where it might, and see if they can be tested.
IF there is light scattering off the edges of the CD & interfering with what is getting into the eye it could improve the accuracy of the representation of what is coming off the CD.
Having a better dynamic balance of the CD could definitly be a mechanism for improvement (particularily in less expensive players) because of reduced modulation of the analog power supplies from the motor contoller supplies. (despite that SY thinks the idea that this might happen is stupid -- if the motor in your fridge can dump crap into the power line that affects sonics i can't see that the more imtimate relation inside a CD player can be dismissed as below consideration)
I would encourage woodturner FGran to try the experiment. For the 2nd mechanism, the angle shouldn't matter, for the former, any scattering would need to be away from the eye.
dave
Using that logic, my PC is an analog device. By virtue of being digital, digital signals have enormous tolerance for noise.
I am not an expert, but am unaware of any transport that clocks off the pits themselves, rather than a clock or PLL. It would seem that as long as the noise was low, any jitter would be due to the pits themselves, not the reading of them. $9.99 cdrom drives do it every day. If any actual experts care to chime in, any correction would be appreciated.
I actually heard a demo of the disk cutter thingy. It made quite a noticeable improvement. Never was it a $1000 improvement, but it did help. They said it used a carbide cutter to cut a 37° bevel on the edge of the disk. Supposedly does something with light scattering and takes out the imbalance. I have been meaning to make a fixture for the lathe to cut an angle on some cds and hear for myself if it makes a damn bit of difference to me at home on my system. Never gotten around to it. Seems better gear is always going to make more of an improvement than that.
I have also played with a radio shack tape demagnatizer used as a demag device for CD's. That changes things. They do indeed sound a bit different. Better? Not really, just different. I stopped using the demag a long time ago and don't miss it.
I find it troubling how people simply crap on an idea just because it is unorthodox or illogical. This whole hobby is completely illogical. We are all freagin' nuts just for doing what we do. I don't play with the treatments and high end high dollar toys anymore, but it bothers me when people cop a huge attitude to those who do. Let's try and keep this civil. Someone asked a question and I'm sure they didn't want someone to rant on about what they think is snake oil (without hearing it) and others to jump in just to bash on the dead horse of things not believed, experienced or tolerated. All of this little stuff makes a difference. The real question is, "is it worth the money and effort?"
I have also played with a radio shack tape demagnatizer used as a demag device for CD's. That changes things. They do indeed sound a bit different. Better? Not really, just different. I stopped using the demag a long time ago and don't miss it.
I find it troubling how people simply crap on an idea just because it is unorthodox or illogical. This whole hobby is completely illogical. We are all freagin' nuts just for doing what we do. I don't play with the treatments and high end high dollar toys anymore, but it bothers me when people cop a huge attitude to those who do. Let's try and keep this civil. Someone asked a question and I'm sure they didn't want someone to rant on about what they think is snake oil (without hearing it) and others to jump in just to bash on the dead horse of things not believed, experienced or tolerated. All of this little stuff makes a difference. The real question is, "is it worth the money and effort?"
True, but is the drive not in a PLL w/a clock? I don't think that mechanism of error would effect jitter and I would not use a drive that did not cache for error correction. Does anybody still make them that way? (Serious question. I have not shopped for a CD player in years.)
(I did catch your "IF" in capitals, just doubt it matters either way.)
Eric
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