Quality of Copied CD's?????

BrentMcGhee

Originally posted by wallstreet
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.

now wait a second!! just what exactly type of mp3 are you talking about that sounds better than a cd. i have done extensive listning tests between cd's and mp3's directly ripped original cd's and found cd's to be the clear cut winner (wich was a no brainer)

Explain exactly what you mean by mp3's being superior and show this documentation you were refering too.

RuSsMaN

Whatever happens guys, keep speculating and theorizing, vs just trying it for yourself.

Amazing.

Mazeroth

Explain this one to me. If you copy computer files from one CD to another, it has to be a perfect copy, otherwise the files won't run. Don't CD burners, in this sense, do a bit-by-bit copy? My brother says when he copies CDs he does it this way, so that every 1 and 0 is read properly and copied perfectly.

Makes sense to me.

BrentMcGhee

Originally posted by RuSsMaN
Whatever happens guys, keep speculating and theorizing, vs just trying it for yourself.

Amazing.

i think we all have we are just comparing each others results now.



i think....

so many people have very strong opinions about this subject and it is very interesting to hear them all, i have heard some stuff so far that i had never heard before and find it quite interesting.

PhantomOG

Originally posted by RuSsMaN
Whatever happens guys, keep speculating and theorizing, vs just trying it for yourself.

Amazing.

I copy alot of my store bought cd's to use in my car and always test the copies in my home system before taking them to the car. They always sounded the same to me.

PhantomOG

Originally posted by wallstreet
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.

So you think a compressed version (an MP3) of the original data is "superior"?

uninformed buffoon?

billbillw

Originally posted by Mazeroth
Explain this one to me. If you copy computer files from one CD to another, it has to be a perfect copy, otherwise the files won't run. Don't CD burners, in this sense, do a bit-by-bit copy? My brother says when he copies CDs he does it this way, so that every 1 and 0 is read properly and copied perfectly.

Makes sense to me.

Data files on CD-ROM have error checksums and other means to verify that 100% of the data is accurate.

PolkThug

Jitter doesn't occur at the laser pick-up assembly, it occurs at the DAC.

jdhdiggs

Originally posted by PhantomOG
So you think a compressed version (an MP3) of the original data is "superior"?

uninformed buffoon?

I do believe that the quote in question is dripping in sarcasm...

wallstreet

Originally posted by jdhdiggs
I do believe that the quote in question is dripping in sarcasm...

Whew.

PhantomOG

Originally posted by wallstreet
Whew.

well at least i wasn't the only one who didn't read it that way

billbillw

Originally posted by PolkThug
Jitter doesn't occur at the laser pick-up assembly, it occurs at the DAC.

Jitter is inherently in the disk though.

Here is a discussion of the varying quality of burn with different media and different speeds. These are the experts talking...
http://www.cdrinfo.com/Sections/Reviews/Specific.aspx?ArticleId=7650&PageId=10
The criteria for a good burns is a combination of low jitter and low C1/C2 errors. If you take the time to read this, it is obvious that not every combination of media and write speeds produces a good burn.

steveinaz

Originally posted by RuSsMaN
Whatever happens guys, keep speculating and theorizing, vs just trying it for yourself.

Amazing.

LOL! Exactly what I was thinking...JUST DO IT! It'll cost you 10 minutes and a blank CD....sheesh.

amulford

I haven't had much luck with it. I like to copy the originals to take in the vehicles, as they normally get more abuse when in them. I seem to have gotten, in almost every one, some sort of skip or pop or something. Nothing totally trashing, but not quite the original.

Maybe I'm burning them wrong???

michael_w

Cool I'll have to try this out and see for myself. I did actually notice that some of my recently burned cd copies (so that I don't have to jack all my dad's cds from downstairs ) had lots of pops and just kind of sounded bad. First I was a little worried that I just noticed this after hooking up my new Monitor 7s but then began to blame it on crappy discs or that I was burning it too fast. Time to slow it down a bit (no more 52x lol) and review the quality.

F1nut

One thing that has not been addressed (I think) is the quality of the CDR used for the copy. From what I understand, a lot of the CDR's available today are pure crap and will not last. As for the sound quailty of a ripped copy vs the original, I've used regular and MOFI's gold CDR's (copies for the shop rig) and even on my main rig I've yet to hear an improvement, in fact I think they sound worse.

Toxis

quality of copied CD's? I've never done a side by side comparison of an original and a copied and had them sound anywhere close. Say what you will "It's all just direct copying 1's and 0's" but you lose sound quality. I hate burning cd's but then again, I support the music industry.

Shizelbs

Well, I've been pretty curious about this all for a while now.

I am going forth with my own single-blind pilot study tonight. Will post results later.

madmax

Very interesting thread! A few things come to mind.

The laser portion of burning/reading a cd is ANALOG, not digital.

It seems to me that jitter is caused when the dac clock is slightly off but I'll have to read more about it.

Sure, the edges may be sharper on a burned CD but it may or may not matter depending on what particular drive is reading it. I assume having sharper edges has an impact. I have to believe it will depend on the exact burners and players used in any given test. Not just the same brand or model, but the exact specimens used.




F1 would be a good one to try several combinations of burns vs originals given his equipment and ears. We should pick a certain CD, copy it with our different versions of burners, burn software, various types of discs and send him the copies to do a comparison. What do you think?

madmax

heiney9

Originally posted by 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

So if the "sharp edges" aren't there to begin with how can copying the "1",s and "0",s replace them. Makes no sense to me at all and I've read just about everything written on digital copying. I used to think the record club cd's were inferior which is not the case. One of the more interesting, especially for Sterophile, articles I've read was in Stereophile about a very careful comparison they did with disc's from the factory vs. discs from BMG and Coulmbia House music clubs.....no difference audibly or measured.

If you use Exact Audio Copy or a similar program that checks the original against the copy before it writes there will be no difference. Media will have more of an impact on sound than anything else other than the burning program itself. For the best results always rip to the hard drive using EAC or similar and then burn to cdr. Direct copy isn't the best way, though it's certainly the fastest. Even then I'd challenge anyone to hear the difference. If you put both in a wave analyzer, like Cool Edit Pro or similar it may show slight differences in the wave form, but it's probably not audible.

Bottom line....use good media, use Exact Audio Copy to rip to hard drive (which is free, do a search on Google for the site) and if your system resources are marginal don't burn a disc while you are doing other things on your computer.

Oh Yeah.... and if you don't like the way your burned disc sounds than spend the money and buy an original

H9

PolkThug

Originally posted by madmax
The laser portion of burning/reading a cd is ANALOG, not digital.

Do you consider it to be analog because the laser is on a tracking mechanism and the disc is physically spinning, or is there something else?

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.

madmax

Originally posted by PolkThug
Do you consider it to be analog because the laser is on a tracking mechanism and the disc is physically spinning, or is there something else?

Burning and reading the 1's and 0's is an analog process. You do not send a 1 or 0 to a disc or read a 1 or 0 from the disc. You read a signal and then determine what it is. This is an analog world, nothing starts off as digital.

madmax

billbillw

Originally posted by madmax
Burning and reading the 1's and 0's is an analog process. You do not send a 1 or 0 to a disc or read a 1 or 0 from the disc. You read a signal and then determine what it is. This is an analog world, nothing starts off as digital.

madmax

PUC...
The laser reads a pit or not. That is a 1 or a 0. That's digital. It is not reading a waveform from the disc, therefore its not analog in any way, shape, or form.

heiney9

Originally posted by PhantomOG
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. [/QUOTE

It's not correcting errors. When you are ripping (extracting) data it's not actually "playing" the info. You are simply copying the digital "bits". There is no error correction (at least not conventional error correction) going on. If you use EAC to extract then you are getting an EXACT copy of digital "bits". All this other BS about sharp edges/dull edges; error correction; spinning error;analog output; adding jitter and all these other "buzz" terms is just not correct. By copying you don't nec alter the bit clock. Clock info is already part of the the "bits" so to speak. Now you can ceratinly correct for jitter at output But no one has been able to prove/measure that jitter can be introduced during the ripping/burning process. I know it seems counter intuitive to believe that, but it’s more true than false. I know all about jitter and it’s effects and bit clock timing so I am informed when it comes to these terms, but it just isn’t an issue when copying. There are many other areas that affect a CDR that you should be concerned with.

H9

PolkThug

Interesting points from everyone.

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

The laser light then is either reflected to or away from the optical pickup. This is interpreted as a 1 or 0, respectively. This is digital.

This data gets buffered up then a digital-to-analog converter is needed to create the wave form.

shack

Burning and reading the 1's and 0's is an analog process. You do not send a 1 or 0 to a disc or read a 1 or 0 from the disc. You read a signal and then determine what it is. This is an analog world, nothing starts off as digital.

Max...Those big black discs you use are NOT CDs. The are called LPs.;) And yes, the first step of the CD reading is pure digital.

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

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

The laser reads a pit or not.

The laser reads the oposite side of the disc from the pits...so it actually reading the BUMPS...not the pits.

Tour2ma

Interesting stuff...

I can see where the sharpness of the pit/ bump could make a difference. The sharper it is the sooner the DAC can determine what it is seeing and at the data rates we're talking about it would reduce "guessing", i.e., error correction.

heiney9

Originally posted by madmax
Burning and reading the 1's and 0's is an analog process. You do not send a 1 or 0 to a disc or read a 1 or 0 from the disc. You read a signal and then determine what it is. This is an analog world, nothing starts off as digital.

madmax

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

heiney9

The “1”s and “0”s are a “map” as to how the analog wave sound be reproduced, a representation. But the “1”s and “0”s are certainly not in and of themselves analog. They are ‘digits’ hence the term digital.

H9