Quality of Copied CD's?????

PolkThug

Originally posted by shack

quote:

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I would consider the actual laser hitting the disc an analog process.

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That is a stretch. This is a digital operation IMO.

On that same note, do you consider shining a flashlight at a CD a digital process, or is it only digital if its a laser light?

Just food for thought, I'm bored at work.:)

AsSiMiLaTeD

Originally posted by RuSsMaN
I bet some of you guys actually think there a little number 1's and 0's on a cd if you could look close enough.

There are...

If you get a really good microscope and a good halogen bulb, you can see all the 1s and 0s right there on the disk



























WAAAAAAAAAAAA!!!:D

shack

Originally posted by PolkThug
On that same note, do you consider shining a flashlight at a CD a digital process, or is it only digital if its a laser light?

Just food for thought, I'm bored at work.:)

Its digital if the flashlight is READING THE DIGITS (ie: the bumps representing the digits).

heiney9

Originally posted by PolkThug
On that same note, do you consider shining a flashlight at a CD a digital process, or is it only digital if its a laser light?

Just food for thought, I'm bored at work.:)

The laser is neither analog nor digital (rather it’s not an issue to be concerned with). Digital refers to how the information is stored on the media (disc). Anybody read about the laser turntable; that’s analog. The laser is simply the “vehicle” which the information (digital or analog) is read or stored. People, there is no analog until the DAC converts the digital info to analog. This is the stage where all the “shaping” “filtering” “error correction”, etc. comes into play. You are all making this “digital” thing to complicated. It gets complicated when processing the info into the analog domain!

H9

Dammit I’m at work and trying not to get caught.

PolkThug

Originally posted by shack
Its digital if the flashlight is READING THE DIGITS (ie: the bumps representing the digits).

The laser doesn't read the disc either. The optical sensor is what does the reading. The laser simply shines on the CD, it doesn't interpret anything.



heiney, we're just friendly bullsh!77ing.

Sami

I agree with madmax, the reading/writing part is analog. The laser is reading the depth of the burn and writing the burn to a certain depth. It's not burning digital information, it is burning something that can be interpreted as digital information.

In this world everything starts as analog. Even on your computer hard drive, all the information is analog. Even the bitmap on computer memory is analog when you think about it. How else could you store it?

PolkThug

Originally posted by Sami
I agree with madmax, the reading/writing part is analog. The laser is reading the depth of the burn and writing the burn to a certain depth. It's not burning digital information, it is burning something that can be interpreted as digital information.

You're leaving out the optical sensor. The laser doesn't read. The optical sensor either gets a reflection or it doesn't, which is stored as a 1 or a 0 in a cache. That piece of the puzzle is digital.

madmax

Originally posted by heiney9
Ok if burning/reading is an analog process….please tell me what the “1”s and “0”s sound like. The end output is ANALOG but the “1”s and “0” are as digital as digital can get. Again if these are analog what do they sound like?

H9

Are you saying to be analog you have to be able to hear it? That is silly talk. Let me re-state: Nothing in this world starts out as digital. Nothing... An analog means of detecting the waveforms always takes place first.

madmax

heiney9

Originally posted by PolkThug
The laser doesn't read the disc either. The optical sensor is what does the reading. The laser simply shines on the CD, it doesn't interpret anything.



heiney, we're just friendly bullsh!77ing.

I know, I hope I’m not coming across to harsh….I’m having fun with this thread too. Not trying to sound to over-bearing. When I’m here at work I have to type fast and don’t always have time to re-read for tone. I am enjoying this very much!:rolleyes:

H9

heiney9

Originally posted by madmax
Are you saying to be analog you have to be able to hear it? That is silly talk. Let me re-state: Nothing in this world starts out as digital. Nothing... An analog means of detecting the waveforms always takes place first.

madmax

Agreed! I misunderstood/misread your meaning. Yes, every sound starts out as analog, is captured thru a mic etc. and then converted to digital and then back again. I was hoping not to introduce THAT side of the equation because that’s a whole other can of worms.

I was literally interpreting that you meant the “1”s and “0”s were analog. You meant they were derived from an analog form. “1”s and “0” are digits that’s all I meant.

H9

Sami

Originally posted by PolkThug
You're leaving out the optical sensor. The laser doesn't read. The optical sensor either gets a reflection or it doesn't, which is stored as a 1 or a 0 in a cache. That piece of the puzzle is digital.

Reflection, analog. Storage of 1/0, analog. 1 and 0 represent digital information but the process is still analog.

shack

The information stored on the disc is in digital form represented by a pit/bump. No sound, No waveform, just information.

The laser/optical reader are for all practical purposes the same thing in a CD application. A device to retrieve stored digital information.

In the most far-reaching definition of analog one might be able to say that the gathering of the information of the 1s and 0s representd by the bumps is an analog process.

Analog (adj.): Of, relating to, or being a device in which data are represented by continuously variable, measurable, physical quantities, such as length, width, voltage, or pressure. (I suppose measuring wheter or not the bump as a physical property is there could meet the definition - but I don't think it is what it is intended to mean)

However the definition of digital (adj.) states: Of or relating to a device that can read, write, or store information that is represented in numerical form.


I too am bored here at work today...I'm going to lunch now...

Sami

Shack, you are correct but the point was to illustrate that the digital world is not all ones and zeros. You need to read that information and the process to do so is analog.

When is it 1? For example when a 0-5V output goes over 2.5V. Or when the surface is 2nm lower than the reference level. Those are all analog.

heiney9

Originally posted by shack
The information stored on the disc is in digital form represented by a pit/bump. No sound, No waveform, just information.

The laser/optical reader are for all practical purposes the same thing in a CD application. A device to retrieve stored digital information.

In the most far-reaching definition of analog one might be able to say that the gathering of the information of the 1s and 0s representd by the bumps is an analog process.

Analog (adj.): Of, relating to, or being a device in which data are represented by continuously variable, measurable, physical quantities, such as length, width, voltage, or pressure. (I suppose measuring wheter or not the bump as a physical property is there could meet the definition - but I don't think it is what it is intended to mean)

However the definition of digital (adj.) states: Of or relating to a device that can read, write, or store information that is represented in numerical form.


I too am bored here at work today...I'm going to lunch now...

Bravo....this sums it up pretty good. I think the confusion some of us are having is that the info is digital, but at some point the process of extracting the digital info is where the analog process takes over. The confusion lies in at what point the digital become analog. The laser reading the "bits" is not an analog process, analog comes later in the chain.

H9

P.S. I've worked up quitre an appetite myself

jdhdiggs

This whole thread, well, its just, wow!

The bumps/pits/whatevers store 1/0 info only that is sampled at a particular bit rate. That's digital. The sampling rate off of the DVD/CDP samples the on off signal at specific intervals. It just reads on/off or 1/0. It doesn't constantly monitor or try to interpret a 0.6 or a duration. It is either on or off. There may be some errors but oversampling fixes those issues. That digital signal is then sent to the DAC and pushed out analog.

Storing the information in the reverse of the process.

As for hardrives etc.. being analog, well, if you mean that with enough digital information you can almost perfectly recreate a analog input (picture, music, etc), well then your right. Other than that, it is about as digital as digital can get: Is the signal above a threshold:1, below:0. That's it...

To the original point:
As Russ said, just try it (Burning CD's)

Otherwise, if you want to talk about the process of reading a CD, just a thought: try reading an authoratative source over conjecture and ramblings.

Edited: Shack nailed it pretty well. People are trying too hard to manipulate definitions beyond their intent.

PolkThug

Originally posted by Sami
When is it 1?

When it is in your CD players cache, before it gets to the DAC.

heiney9

Oversampling doesn't "fix" the errors. The error's are still there. In simple terms oversampling pushes them out of the audible range, so they appear they are not there. My ramblings come from having read numerous factual articles/discussion's on the subject over the past several years. I admit that I am still very limited in my knowledge and we are just scratching the surface of this issue. It's still fun:)

H9

heiney9

For those who really want to get into this Digital World and understand it, I have several links to published documents and analysis. The links are at home and I'll post them tonight, FWIW.

H9

Sami

Originally posted by PolkThug
When it is in your CD players cache, before it gets to the DAC.

And that information in the cache is still analog information in the end. When in the cache is that bit 1 or 0.

heiney9

Originally posted by Sami
And that information in the cache is still analog information in the end. When in the cache is that bit 1 or 0.

Depends on if the cache is before the conversion or after the conversion to analog

H9

faster100

You guys are making a relativly simple thing more complex then need be, If your that worried about copy quality stick with the original...

Sami

Originally posted by heiney9
Depends on if the cache is before the conversion or after the conversion to analog

Please explain.

heiney9

BEAT







DEAD







HORSE


:eek:

jdhdiggs

H9: By fix, I mean a missread on one of the samples. If you have a particular failure rate for reading a "hazy" bit, oversampling that bit gives you a great oppurtunity to read the correctly interpret information. I suppose "fix" was the incorrect word.

The cache question, it's stored digitally as a bunch of 1's and zeros until through the DAC.

Done flogging the deceased equine.

heiney9

Originally posted by Sami
Please explain.

Ok typically the cache is used to store the information so that the output of the device (cd player) can be delivered without interruption. The cache stores the “bits” (1’s and 0’s ) as a ‘staging area’. It helps provide a constant bit stream to the DAC portion of the cd player. On the converse a portable cd player or portable mp3 player may use a buffer (a cache of sorts) stores analog information so if the player is bumped it won’t skip. Those are examples of both types. My description is simplified for brevity. But that’s the point anyways

H9

Sami

Originally posted by jdhdiggs

The cache question, it's stored digitally as a bunch of 1's and zeros until through the DAC.

It is digital information but the storing is analog. You cannot store digitally, it is always some kind of analog information in the end. That's my point.

RuSsMaN

SERENITY NOW!!!!

You guys will argue about anything, HILARIOUS.

jdhdiggs

Originally posted by Sami
It is digital information but the storing is analog. You cannot store digitally, it is always some kind of analog information in the end. That's my point.

Got ya now!

Analog is always the start and end, that's your point. Even though the actual information is digital, it is a representation of the original analog. That I'll agree with..

Sami

Originally posted by jdhdiggs
Got ya now!

Analog is always the start and end, that's your point. Even though the actual information is digital, it is a representation of the original analog. That I'll agree with..

That and the storage of the digital information. Even when you take the analog information and convert it to digital, the digital bits are stored analog. Hard drive for example is used to store digital information but it's a magnetic device meaning analog. Same with CD's.

PolkThug

Originally posted by Sami
It is digital information but the storing is analog. You cannot store digitally, it is always some kind of analog information in the end. That's my point.

The storing is digital, the stored sequences are either "on" or "off" and it has no moving parts.