Quality of Copied CD's?????

BrentMcGhee

I have gone back and fourth with this for a while now. I thought that copying all of my friends cd's would be a quick way to grow my cd collection, but i am a little hesitant.

I know that a cd is just a bunch of 1's and 0's so theroretically when it gets copied directly (not being ripped to the computer first just a direct disc to disc copy) it is just duplicating all of the 1' and 0's. So therefore one would think that it would be an exact copy with no audio quality lost at all.

However i have done some serious listening back and fourth between an original cd and a direct copy, i very vaguly think i can tell the difference between the two but i do not know if it just because i know wich is wich and the placebo effect is kicking in.

Has anyone else done any experimenting with this or know smothing that i dont????

PolkThug

Its a data transfer with error checking (assuming you don't disable it), there is no difference.

gregit

http://www.riaa.com/issues/piracy/default.asp

BrentMcGhee

Originally posted by gregit
http://www.riaa.com/issues/piracy/default.asp

damn!! i am at work and i cant access that site. Our firewall is set up so we can only go to sites that are on an pproved list.

What is the jist of that site.... i will check it when i get home

jdhdiggs

I'll save you some time:

It basically says that what you are doing is illegal and that if you want the music, you should buy it and not burn your friends. Otherwise the lawyers get to play with you.

hoosier21

the jist

(in my best Mr. Mackey voice)

piracy is bad, ummkay

tryrrthg

I've seen some threads over at audiogon that people are saying that their copies sound better than their original. I think the jist of it is they feel if they burn the copy at a slow burn rate they get deeper pits in the CD which gives them a better sound.

steveinaz

I don't know why either, but I notice especially with poor sounding original CD's, that they sound better after being copied to a writeble CD.

RuSsMaN

On a standard Redbook, a copy will almost ALWAYS sound better.

Why?

In a nutshell, the Redbook is never actually 'burned' with a laser. They will burn the first few, and check to make sure they burned correctly - then they will make a template from the good burned copy - and simply 'stamp' out the rest.

When a CD is stamped, rather than burned, especially far into the production run as the template is worn down - it looses the sharp edges of the original - BUT since it is 1's and 0's - the data is still there.

When you 're-burn' the cd (with YOUR laser), you not only pick up all the data, but since you are doing an actual burn, not a stamp - you put BACK the sharp edges on the data that the stamping process lost.


Cheers,
Russ

NCrewson

The legalities of copying also depend on where you live. Here in Canada the courts have decided that it is illegal for me to copy my CD and give the copy to you (redistribution), but it is not illegal for me to lend you my CD have you copy it and keep the copy for your own personal use. Likewise it is not illegal to download music from the internet for personal use, only to upload it.

BrentMcGhee

say whhaaaaa.....

so from what i am hearing i am actually improving the sound by copying original cd's. I have neve heard that before and it is kind of hard to beleive.

If that is the case then i should just take every cd i have already bought as well as any others i am going to buy and reburn them and just throw the originals on a shelf somewhere?????

Can anyone back this up, like they have heard it before somewhere else?

exalted512

im never letting the popo looking at my cd case...or my dvd case for that matter...
-Cody

billbillw

I have to disagree with Russman.

A copy usually not be better and I have many copies to prove that.

In theory, when you make a copy, you are reading the 1s and 0s and exactly duplicating them. Sadly, this does not happen. Errors are introduced in both the ripping stage and in the burning stage and many of them cannot be avoided unless you have the very best drives available.

Some drives read the audio very good and can extract a very clean image of the original disc. Likewise, some drives do very poorly at audio extraction. Most of the time, unless you have done a significant amount of research at sites like www.cdrinfo.com, you will not know whether your drive is good, bad, or average at ripping audio.

On the same note, even the best burners out there will introduce jitter and land errors that were not in the original source. This is heavily reliant on the media type, the quality of the burner, and the firmware.

Ideally, if you optimize everything and have good equipment/media, you will get a copy that is not audibly different than the orignal. I highly doubt that you will get a copy that is better than the original unless you are trying to salvage a disk that is scratched to the point where it affects playability.

I don't buy the late production run/worn template theory. Even if that is true, the laser in your burner does not burn perfect sharp edges. Read into any of the detailed articles at cdrinfo that analyze the quality of a burned CD and you will see this is not true, no matter what spead the burn was performed at.

steveinaz

Russman's observations are exactly what I read on the subject, about pits being cut "sharp" when re-burned. Makes sense to me, and I have witnessed it with my own 2 ears.

My Dave Mason CD is a shining example of this. My burned copy sounds far better/smoother and fuller than the original CD.

Skynut

Originally posted by hoosier21
the jist

(in my best Mr. Mackey voice)

piracy is bad, ummkay

in my best Mr. Mackey voice

don't pirate music ummkay

BrentMcGhee

Yeah well even with piracy beeing (well illegal) i still do not see me stopping to copy my friends cd's unless it isproven that a copy is far inferior to the original store bought one.

Now dont get me wrong i still buy cd's on occasion if it is a cd i really like, but at the cost of cd's and could never afford to buy all the cd's i want. Cd's are way to expensive. I mean c'mon it probably costs them maybe a few cents to make each cd and they turn around and charge us 14 dollars to buy it. talk about a markup. I would love to be able to own all orinals but i just can't.

Now billbillw these errors that you are refering to during the burning and ripping process. even with errors if there are any are they audible difference or wont the error detection built into cd players take care of them just as they do with an original.

PhantomOG

Originally posted by BrentMcGhee
I mean c'mon it probably costs them maybe a few cents to make each cd and they turn around and charge us 14 dollars to buy it. talk about a markup. I would love to be able to own all orinals but i just can't.

a few cents for a *blank* cd. do you think the music that is recorded on the cd just magically appears there for free?

whether or not artists are overpaid is a different question, but if creating music isn't going to make any money for artists, no one would do it and you wouldn't have anything to listen to.

billbillw

Now billbillw these errors that you are refering to during the burning and ripping process. even with errors if there are any are they audible difference or wont the error detection built into cd players take care of them just as they do with an original. [/B]

Your player SHOULD remove them, but the error correction is different in every player. Some just meet the Redbook standard, and some go beyond.

Several years ago, I was burning many copies with a TDK 32x burner that I though was doing a find job. The disks all played fine on my Sony player, in my car, etc. Then, as my Sony player was dying, I bought a Marantz player. When I played the TDK burned disks, there was terrible static (jitter) in the playback. I thought the Marantz player was defective. Every one of my origninal pressed disks played perfect, all of the disks I burned with an older Sony 8x burner sounded great. The only disks that had the jitter were the ones recently burned on the TDK. After experimenting around quite a bit, I figured out that my TDK burner was just making crappy copies when I let it burn at the full speed 32x. That combined with the fact that the Marantz player doesn't use as much error correction as the Sony player is why I discovered the problem. According to Marantz, less error correction gives a truer, more musical playback of CD.

When I backed it down to 16x with the TDK, the copies played perfect. The funny thing is that I could take a copy that was burnt at 32x, rip it, and reburn it at 16x and it would play fine. The computer was able to rip a clean copy despite the jitter. Since then, I have replaced the TDK burner several times over. An NEC 4x DVD/16x CD burner, a Liteon 8x DVD/40x CD burner, a Benq 16x DVD/40x CD burner, and none of them have given me disks that playback on funny on the Marantz.

I guess there may be some truth in what Russ said, but the quality of your ripper, burner, and media all have to be top notch. I still debate whether EVERY copy will sound better. Maybe SOME copies sound better.

Shizelbs

My question is this, in a digital system, why would a deeper pit be interpreted any differently?

Spawndn72

When you are refering to "error correction" are you refering to oversampling? The reason I ask is becasue the way oversampling works is the reader reads the bit 8 times(for 8x oversampling) then it takes what ever it read the most, a one or a zero, and goes with that. So if a bit is burned wrong the oversampling is not going to catch that. It only catches read errors.

Spawndn72

My question is this, in a digital system, why would a deeper pit be interpreted any differently?

Becasuse if a pit is not deep enough, the laser might not notice it is there.

steveinaz

It's not the depth, ****, but the sharpness of the outlining edges that is important.

See for yourself. Find a real glarey, flat sounding CD in your collection (Nazareth Hair of the Dog and The Best of the Guess Who comes to mind) and burn that sucker on a CDRW. The A/B it with the original---tell me what YOU hear....

FWIW I have a $60 Asus burner--nothing fancy.

PhantomOG

Originally posted by Spawndn72
Becasuse if a pit is not deep enough, the laser might not notice it is there.

so then people who believe this also believe that their el-cheapo CD-ROM drive in their computer they use to copy the CD is better at reading discs than their high-dollar "audiophile" CD player?

that seems a bit silly...

PhantomOG

Originally posted by steveinaz
It's not the depth, ****, but the sharpness of the outlining edges that is important.

is there a difference between a "sharp" one and a "dull" one (binary) if they are both read by the player as a one? seems like this stuff would make sense for an LP (analog), but i'm not getting how it would translate to a digital CD.

steveinaz

Originally posted by PhantomOG
so then people who believe this also believe that their el-cheapo CD-ROM drive in their computer they use to copy the CD is better at reading discs than their high-dollar "audiophile" CD player?

that seems a bit silly...

No, what's happening is your computer's CD is correcting the errors before being written on to the new blank CD; so you get a "fresh" representation, with clean edges and proper depth.

The theory is that the dies used to press mass produced CD's begins to wear out, therefore the edges are not rendered as cleanly as the original burned master.

BrentMcGhee

So let me see if i can recap everything that has been said so far.

For the most part anytime you do anything with a cd (ripping, burning or even playing it ) whatever laser you are using may read it differently each time and produce some jitter or read errors one time, and then not another time with the exact same laser and player and dacs etc. etc.

So in the end a burnt cd is not really any better or worse than the original (as long as your burner is not a really crappy one). Becasue yes some misread 1's or 0's may be put on the copy that were not on the original cd but who is to say that the first time that cd was burnt from the original the laser did not misinterpret some of the information. And also along those same lines then when you are playing an original the laser might mis interpret what is on the cd so you are still getting some errors even on originals.

It seems to me that whether the cd is a copy or not does not matter. What is effecting the quality of the cd is the equipmnet that you are playing it on.

i.e. Original Cd on Crappy equipment = crappy sound
Copied CD on great equipmnet = Great sound

steveinaz

Originally posted by PhantomOG
is there a difference between a "sharp" one and a "dull" one (binary) if they are both read by the player as a one? seems like this stuff would make sense for an LP (analog), but i'm not getting how it would translate to a digital CD.

All I can say is give it try. If I knew why it works, I wouldn't be working in a warehouse for Uncle Sam....:D

PhantomOG

Originally posted by steveinaz
No, what's happening is your computer's CD is correcting the errors before being written on to the new blank CD; so you get a "fresh" representation, with clean edges and proper depth.

The theory is that the dies used to press mass produced CD's begins to wear out, therefore the edges are not rendered as cleanly as the original burned master.

how is the computer correcting errors? are CD's encoded with ECC? and if the computer CD-ROM can correct errors, why can't a stand-alone player? ECC is relatively easy stuff compared to all the other bells and whistles in an expensive stand alone CD player.

Sami

Originally posted by PhantomOG
is there a difference between a "sharp" one and a "dull" one (binary) if they are both read by the player as a one?

There is the problem, "if". Sharp hole is more likely to be read correctly while some players might read the dull as if it wasn't there.

I don't know much technically about the burners/readers but I would assume the error correction is when you read that same section multiple times:

1. 11010001
2. 11110001
3. 11010101
4. 11110101
5. 11010101

When you OR these together, or whatever the error algorithm is, you will get what the player assumes is a correct bitmap:

C: 11110101

wallstreet

It also has to do with the digital logic implemented by the DAC's. In some cases, pits out of Redbook standard cause an error in the DAC processor. For example, when examining any two bits the CRC (Cyclic Redundancy Check) performs exclusive OR (XOR) operations to ensure data integrity. As a quick reminder, the XOR truth table looks like such for inputs A and B.
A B Result
0 0 0
0 1 1
1 0 1
1 1 0
If the dull pits are misread (e.g. stamping, shallow square pits, R/W disk, etc) then the resulting data byte can be exponentially altered. This problem is inherit in any digital burning process in use today (including SACD's). What you should be doing is making MP3's. The documented superiority in sound quality of MP3 makes this decision a no-brainer. Anyone disagreeing is an uninformed buffoon who you should discredit immediately.

billbillw

The CD "reader" in your computer can spin much faster and it can go over, and over, and over, , a given section of audioand slow down if neccesary to extract the data. That is how it reads it better than your stand alone CD player.

I should have clarified above, that most CD readers today, whether it is a burner or just a reader, do a pretty good job of extracting audio. A few years back, it was hit or miss.
So today, assuming your computer drives are less than 3 years old, you will probably get a very accurate rip from the original CD, unless it is severly damaged. Most of the errors in a burn will end up coming from the burning process. The burners today still vary in their quality, but most are capable of making a good burn if your firmware is updated, your drives are defragged, you have enough memory, and you are using decent black media. There are a lot of variables that can end up causing a bad burn, but for the most part, bad burns are much less common than just two years ago.