CD Dupplicating vs Ripping

[theo]

Dear Experts,

I am new here but I have been using dbpoweramp for quite a while. So I understand why error pointers helps to get a good rip out of badly scratched CDs and also the various features like C2 error correction and cache disabled drives gives better results etc. but one thing I cannot understand is whether a CD to CD copy is a lossy process i.e. if we take a CD and keep duplicating one from another, are we moving away from original?

Also, back in 2006 when streamers first starting appearing, there was a significant group of the hifi crowd who did't quite accept that (at least the better ones) were better than CD players. Do we still have forum members here who still stand by that argument that CD players are better. Obviously, I am not being specific enough e.g. model brand etc. but I just wanted to know what the general opinion is now.

Thanks

[garym]

Re: CD Dupplicating vs Ripping

Streamers and DACs with lossless files have long ago progressed to the point where there is no difference in Sound Quality between these and a CD player (of any quality, including big $$$$ CD players). Keep in mind that whether a CD Player or a Streamer, the issue is to read a digital file (from a harddrive or from a CD-ROM) and deliver that digital file in a 100% bit perfect manner to the DAC (whether the DAC is inside the CD Player or Streamer or a separate DAC attached to either). If the streamer delivers a bit perfect stream to the input of the DAC (easily tested by the way), then as long as the DAC does its job (and most modern DACs do), then there would be no difference between a CD player and network streamer. Of course once the audio is LEAVING the DAC (now as analog), the sound quality is a function of how well the analog chain works.

Shorter answer: there is NO difference in theory and in practice one would only find differences if there is a really crappy DAC. Also note that "streaming" problems don't create subtle changes in sound quality. If your network is not working properly, you'll have dropouts, buffering, etc., not "loss of highs or muddiness or loss of soundstage.

Regarding copying CDs and loss due to generations of copies. At a practical level, ripping or duplicating a CD to lossless digital files is perfect and no matter how many times this is done (generations), you'll still have bitperfect copies. These are not cassettes or reel-to-reel tapes where each copy loses something and several generations away from the original, one has much lower quality.

I say "practical level" because technically there some possibilities that *may* make a digital copy different if burned back to a CD rom. The tracks are the same (bit perfect), if gapless songs, they will still be gapless, etc. But if one wanted to take the digital files and recreate the exact CD by burning the files back to a CD-ROM, then there are some technical things related to hidden tracks, offsets, read into lead in/out, etc. You'll need to read up on the technology of how a CD player reads a disk, with markers, etc. But again, if one RIPS the files from a CD, a good ripper (dbpa, cuetools, EAC) can create 100% bit perfect, gapless (if in original CD) digital files.

p.s. There are folks in the "hifi" crowd that refuse to give up on their "analog" view of the world and try to apply analog concepts/issues to a digital context. This doesn't work of course. And folks that have spent a lifetime tweeking their analog gear to get better sound have a hard time dealing with the fact that much cheaper digital stuff (DACs, etc.) can solve all those old analog problems. I know, I've been there. I'm an old guy so I lived the days of having turntables that cost more than my car, sitting on slabs of granite for stability, etc.

[theo]

Re: CD Dupplicating vs Ripping

Thanks for the feedback garym.

Lets take a simple example. Suppose we have a scratched CD. Now we try to rip this and all the error correction mechanisms come into play which means there is a chance (however small that may be) that some samples will need to be "error corrected" simply because the scratches have made it impossible to read what was originally there on CD. Now suppose we also take a CD to CD duplicate of this CD. In this instance, am I right to assume that the duplicate CD will also be an inferior version of what was there on original CD (before it got scratched) and it will be the same with the ripped result?

Generally speaking, I guess what I am asking is if a particular CD can be ripped without loss, then can we also assume a duplicate of the CD will also be true to original. And that the inverse is also true i.e. if it so happens that even with all the error correction mechanisms of CD e.g. C2 etc., if a certain CD cannot be ripped without loss (due to physical damage or marks on CD) then even CD-to-CD duplicates will suffer a similar loss.

[Spoon]

Re: CD Dupplicating vs Ripping

>if a particular CD can be ripped without loss, then can we also assume a duplicate of the CD will also be true to original

Yes, this is why AccurateRip was created, see www.accuraterip.com

[garym]

Re: CD Dupplicating vs Ripping

Thanks for the feedback garym.

Lets take a simple example. Suppose we have a scratched CD. Now we try to rip this and all the error correction mechanisms come into play which means there is a chance (however small that may be) that some samples will need to be "error corrected" simply because the scratches have made it impossible to read what was originally there on CD. Now suppose we also take a CD to CD duplicate of this CD. In this instance, am I right to assume that the duplicate CD will also be an inferior version of what was there on original CD (before it got scratched) and it will be the same with the ripped result?

Generally speaking, I guess what I am asking is if a particular CD can be ripped without loss, then can we also assume a duplicate of the CD will also be true to original. And that the inverse is also true i.e. if it so happens that even with all the error correction mechanisms of CD e.g. C2 etc., if a certain CD cannot be ripped without loss (due to physical damage or marks on CD) then even CD-to-CD duplicates will suffer a similar loss.

You are making the incorrect assumption that ripping a CD to digital files somehow "corrects" problems. This is generally not true. All the rereading, C2 error reporting, etc. is not "correcting" the errors found but simply *reporting* the errors found and trying to reread frames enough times to get consistent reads and then use that info. The only place in dbpa that I'm aware of where there could be any "correcting" going on is in the options to ripping under "secure" options where there is a place to tick "Interpolate Unrecoverable Frames". I leave this unticked.

So the dbpa rips either match AR database (best outcome) or are "secure" rips not in AR (2nd best) or are "warning" where dbpa had some trouble reading some frames, but eventually got consistent reads after some retrying (3rd best).

A "duplicate" CD (meaning I guess a disk image copy?) could potentially be without loss. Although actually you have fewer mechanisms to tell you whether that CD image is actually without loss (as you do NOT have AR or even the other mechanisms within the dbpa ripper at play when you are simplying making a single disk image). Given this, the ripping of a CD with a secure ripper (such as dbpa, EAC, cuetools) is likely much more secure in confirming a bitperfect rip than a "copy" of the CD image.

[garym]

Re: CD Dupplicating vs Ripping

>if a particular CD can be ripped without loss, then can we also assume a duplicate of the CD will also be true to original

Yes, this is why AccurateRip was created, see www.accuraterip.com

If there was a Nobel Prize for digital audio, the accuraterip inventor would clearly be an eventual recipient!