Quality of Copied CD's?????

PolkThug

The answer to everything is 42.

Sami

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

The stored bits are analog.

shack

Originally posted by PolkThug
The answer to everything is 42.

Of course as a binary number that should read:

The answer to everything is 101010.

PolkThug

Originally posted by Sami
The stored bits are analog.

A bit is digital.

Sami

Originally posted by PolkThug
A bit is digital.

You're missing the point. The way it is stored is analog. How do you store digitally?

PolkThug

Originally posted by Sami
You're missing the point. The way it is stored is analog. How do you store digitally?

This thread has a point?

Sami

Originally posted by PolkThug
This thread has a point?

Yes, it does. There is no such thing as pure digital.

PolkThug

Originally posted by Sami
Yes, it does. There is no such thing as pure digital.

I have no idea what "pure digital" is.

heiney9

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.

No I don’t think so, at least from what I understand. The cache I’m referring to is the cache (buffer) that is storing the “digits” before they are fed for conversion to analog. In order for the output (analog) to remain constant, the bit stream (digital) has to remain constant. Hence the info is “held” (stored) in the cache. Now this may be also done after conversion to analog for error correction purposes, etc, so I suppose it can be both ways depending what side (digital or analog) of the circuit you’re on.

H9

Ok I’m done for now I gotta get some work done!!

PolkThug

Yeah, but why do the Sith use synthetic Illium crystals in their light sabers, and the Jedi use naturally formed crystals?

Sami

Originally posted by heiney9
No I don’t think so, at least from what I understand. The cache I’m referring to is the cache (buffer) that is storing the “digits” before they are fed for conversion to analog.

You have to look at the cache itself and what it is. It's an analog device in the end.

PolkThug

Originally posted by Sami
You have to look at the cache itself and what it is. It's an analog device in the end.

So, are DAC's just a conspiracy?

heiney9

Originally posted by PolkThug
So, are DAC's just a conspiracy?

Absolutely........It says so in the owner's manual

LOL

heiney9

Originally posted by Sami
You have to look at the cache itself and what it is. It's an analog device in the end.

So the cache must be AFTER the digital conversion to analog. You can't be saying that analog conversion takes place TWICE in a DAC? That's just redundant and doesn't accomplish anything.

H9

madmax

I have a headache after reading all that. Can we at least agree the disc spins?
madmax

PolkThug

Originally posted by madmax
I have a headache after reading all that. Can we at least agree the disc spins?
madmax

Actually, it rotates.

madmax

After thinking about it, everything in a computer is strictly analog except for the data which is being passed.
madmax

heiney9

Originally posted by madmax
I have a headache after reading all that. Can we at least agree the disc spins?
madmax

Actually inertia causes the round object to rotate in a clockwise or counterclockwise direction speeding up and slowing down based on where the laser assembly is in realtion the the diameter of the round thingy (disc).



H9

PolkThug

Originally posted by madmax
After thinking about it, everything in a computer is strictly analog except for the data which is being passed.
madmax

Is there anything in a computer that is neither of the above?

heiney9

Originally posted by PolkThug
Is there anything in a computer that is neither of the above?

My stash of **** is neither of the above

H9:p

billbillw

Originally posted by PolkThug
Yeah, but why do the Sith use synthetic Illium crystals in their light sabers, and the Jedi use naturally formed crystals?

I believe the only source of natural crystals was in a Jedi Temple on the planet Illum, the location of which was a closely guarded Jedi secret. The Sith would not be able to obtain the natural crystals without letting their identity and prescence be known. During the Clone Wars, Count Duku gave up the location of the Jedi Temple on Illum and it was destroyed by an army of cloaked droids.

michael_w

Originally posted by RuSsMaN
SERENITY NOW!!!!

You guys will argue about anything, HILARIOUS.

lol it's so true. But hey at least I'm learning by reading all of this it's digital but is it really digital stuff.

heiney9

Originally posted by billbillw
I believe the only source of natural crystals was in a Jedi Temple on the planet Illum, the location of which was a closely guarded Jedi secret. The Sith would not be able to obtain the natural crystals without letting their identity and prescence be known. During the Clone Wars, Count Duku gave up the location of the Jedi Temple on Illum and it was destroyed by an army of cloaked droids.

Hey Guys.....Don't be ruining the new Star Wars movie for me. I haven't seen it yet!!:cool:

The add in the paper says coming to a DIGITAL theater near you! What does that mean????

H9

dragon1952

"I'm analog, I think I'm analog, therefore I am, I think."

"Of course you are my bright little star,
I've miles
And miles
Of files
Pretty files of your forefather's fruit
and now to suit our
great computer,
You're digital freakin' trash.


"I'm more than that, I know I am, at least, I think I must be."



"There you go man, keep as cool as you can.
Face piles
And piles
Of trials
With smiles.
It riles them to believe
that you perceive
the web they weave
And keep on thinking free."

Jstas

WOW!

*sigh*


WOW!


If the "digital" discussion is finished, only a few have gotten it right. Computers are not analog instruments. They rely on boolean logic as a basic form of creating a program. These programs control everything from memory address assignment in hexadecimal nomeclature down to what color should the pretty pictures be.

There is NOTHING analog about a computer or the data it handles. You can pass an analog signal to a computer but it does not record the analog signal. It samples the signal at a certain bitrate. It then records that smaple signal in some sort of format like .WAV, .CDA, .WMA and so on. Given that, ALL music is stored in a compressed format. The compression factor is usually listed as a percentage. Sound stored in an "uncompressed" format is merely stored at 0% compression. The reason this occurs is because EVERY operating system out there manages data space. To store the data in the data space, the computer must be able to read it and use it in its dataspace. Since that dataspace is not raw space, the media is being stored within the constructs of the operating system. Because of this, the computer indirectly manipulates the file to ensure that it will fit within the constructs of its data management system. In other words, the files have to fit in the format of the block sizes and addresses of those blocks. The OS will break up a file and allocate it to those blocks to ensure that it fits the logical map it lays out for the data space.

Now, CD's, no matter what twisted way you want to bastardize the definition, are digital. They have an analog source in the artist itself but once that signal comes off of the session tape and into the computer to be pressed in the mill, it is digital. The CD is not burned from an analog source. It is burned from a digital sample of an analog source which is stored on a digital form of media called a hard drive and loaded into a "cache" for burning which is stored on ANOTHER form of digital media called RANDOM ACCESS MEMORY. The session tape is usually sampled at 128-192 kbps. That is then burned on to a master disc which is then copied and sent to press. The DIGITAL signal on the CD is then read off of the master copy and loaded into the memory of the mill which then either presses or burns every copy of the disc from there. The quality of the actual recording is determined by the quality of the DAC on the system that makes the master copy of the CD from the master tape from the recording session. It would require entirly too much overhead and a computer system the size of your average clustered Cray to be able to do the analog to digital conversion on the fly for each copy of the master CD and still burn/press all the CDs that are going to market.

CD's are an inherently poor recording media because of the fact that they are SAMPLED and not the actual audio. Sampling is the way a digital-audio converter reconstructs the analog signal from the digital sample. It starts out by taking a sine wave and mapping points along the wave at 192 thousand points per second for a 192 kbps sampling rate. These points are then recorded as the sample of said sine wave. They get stored as a digital signal. THAT SIGNAL IS WHAT IS WRITTEN TO THE CD! It's a digital signal and it is written digitally, stored digitally and read digitally! That's it! There is no analog when it comes to writing and reading a CD. The source is analog and the result is analog but the CD is digital.

When the CD is read, it gets cached and stored for the D/A converter to read and intepret the digital sample of the analog signal. The converter takes that map of points and then reconstructs a stepped sine wave instead of the analog signal. The D/A Converter then fills in the slope by playing connect the dots of those sampled bits. It does this by building smaller steps in between the peaks of the digital signal. The reason the bitrate of the D/A converter is so important is because the higher the bit rate, the higher the density of those little peaks between the sampled peaks of the signal being passed to the D/A converter. The higher the density, the less space there is then the closer they are together. The closer they are together, the more accurate the representation of the sine wave becomes. The point is to eventually get to a point where the space between the peaks is so short that the difference between the analog and digital signal is completely inaudible. This is entirely possible but it requires an immense amount of space. Much more than would fit on a CD.

Speaking of sampling, this is what makes MP3's so poor. When you sample and compress a CD track, you are sampling a sample of an analog signal. You are making a copy of a copy. You are losing much more information. This is why you should be jacking that sampling rate on the MP3 ripper as high as it will go. This will minimize the amount of data loss in the sampling process and you can wind up with an MP3 that is actually very close to what is actually on the CD.

Bottom line, an LP is analog because it is a physical groove that is a direct representation of the analog source. It is made by vibrating a needle that cuts the wax in the same shape as the vibration of the sound from the analog source. That wax is then copied in a mold and pressed into vinyl and made into LP's. They are read by running a fine needle in the grooves of the vibrations produced by the analog signal. That vibration is then transferred directly from the turntable to the amplifier or pre-amp. It is unmolested when playing from your speakers. A digital format like a CD CONVERTS that analog signal BEFORE it burns the CD. It writes a digital signal which then requires intepretation and conversion. ALL of the errors in your typical CD recording occur in the conversion and intepretation stages. That is also where error correction is applied. An analog audio system reads the continous unbroken signal of the source and reproduces it exactly as it read it. A system with a DAC in it does not read the continous analog signal but a broken up sampling of the signal. That is what is different and that is why you can't cram an LP into a CD player and get a results that resembles music. They are two different instruments that start from the same point but take completely divergent paths to reach the same result.

The depth of the holes in a CD make no difference. There is no measurement of the depth at all. I don't know who came up with that cockamamey idea but it's bunk. Forget you ever heard it. A CD and all other digital formats have two phases, true or false. There is no in between. It is a reflection or no reflection. The only other state is an error state and that occurs when the reader cannot determine if it found a reflection or not. It contradicts the true/false statement but only because it is over simplified. The depth of the hole doesn't matter. What matters is how completely the hole was cut. The laser is bounced off the CD and the light is returned to the sensor. That sensor then reads the intensity of that light. It has to match a certain number to be true. If the hole is incompletely cut, the intensity of the light may be greater than a specified range or refocused. The computer then cannot determine if this is a true reflection. This is because for a true state to exist it needs to match that exact range of intensity and for all intents and purposes, it will. If the intensity is lower than the specified range for true then it is false and read as no reflection. The errors occur when it exceeds the range. The computer then knows that there is a reflection but it is outside of normal parameters. This can be caused by scratches and dings which have sharp leading edges. These edges can focus the laser light and increase intensity. The error correction then gets called up to say if it really is a reflection of not. You get skips when you have too many bits in a row that are errors and cannot be intepreted. That is when your oversampling and error correction come in to play. It has already been explained so I'm not going over it again. However, the sharp edge problem is why things like Disk Doctor work so well. Remove the edges and you soften the refraction of the laser and then reflections can be brought back into the proper range.

Now, this is the umpteenth time this has been explained in this thread by several people. Do you think you can try to understand it this time and quit trying to re-write physics to meet your own little bass ackwards world?

Jstas

And now!

A LINK!


http://www.usbyte.com/common/compact_disk_4.htm

Ain't the internet great?




Oh, by the way, these are white papers written by the wonderful people who CREATED the technology known as Compact Disc.

Crazed

Electricity is analog, light is digital (photon packets). Both can be expressed or perceived as either analog or digital.

Crazed

Well, as I read it, that page introduces time into the equation, now making the signal analog.

steveinaz

This is still going on?

Use the two highly specialized instruments located on each side of your head, they're called ears. They have never been replicated nor replaced. They will show you to the light. The light that holds knowledge beyond measurable tolerances, the light they call subjectivity.

What's the Polk Forum Creed?

"Those who don't know, don't know that they don't know"

AsSiMiLaTeD

Originally posted by steveinaz
This is still going on?

JESUS CHRIST!!!

I was thinking the same thing...

we're beyong beating a dead horse here, we're now dismembering its dead rotting carcus...