best free software to duplicate CD's?
February 21, 2010 6:46 PM Subscribe
Best free software for duplicating CD's?
I have finished producing an album for a friend, and she wants to make the copies of the CD herself. I have a master CD that is ready to be copied, but she doesn't have any software that will make an exact duplicate copy, just software that will rip the files, and then burn them on an audio CD (which is not what we want).
Is there a good free program that will duplicate CD's? All it needs to do is make an exact duplicate of the CD we have, no more, no less. She is not very computer savvy, so the easier it is to use the better, but we're looking for free software if at all possible.
She is using windows, I believe XP but possibly vista.
I have finished producing an album for a friend, and she wants to make the copies of the CD herself. I have a master CD that is ready to be copied, but she doesn't have any software that will make an exact duplicate copy, just software that will rip the files, and then burn them on an audio CD (which is not what we want).
Is there a good free program that will duplicate CD's? All it needs to do is make an exact duplicate of the CD we have, no more, no less. She is not very computer savvy, so the easier it is to use the better, but we're looking for free software if at all possible.
She is using windows, I believe XP but possibly vista.
InfraRecorder will do this. But copying a physical audio CD is always going to be slightly problematic; the same format deficiencies that make good ripping hard to achieve also make good duplication hard to achieve. She will get far more reliable (and quicker!) burns working from a copy of the hard disk image file that you presumably used to burn the master than from a physical master CD.
posted by flabdablet at 7:00 PM on February 21, 2010 [1 favorite]
posted by flabdablet at 7:00 PM on February 21, 2010 [1 favorite]
The absolute best program I've found for this purpose, bar none, is Exact Audio Copy. It will produce the highest-quality WAV files, with the least errors, of any program I know of and have tested. These can then be burned to a new CD. This can take a long time if you do it to high standards (a few hours, sometimes) but it is the best way.
InfraRecorder is much more user-friendly, however. It incorporates a nice GUI with copying functionality. flabdablet is right that errors are more likely, but they are still relatively rare, so long as you're using good CDs. With InfraRecorder, you won't be ripping MP3s and burning them; you'll be producing good WAV files and burning them.
posted by koeselitz at 7:20 PM on February 21, 2010 [1 favorite]
InfraRecorder is much more user-friendly, however. It incorporates a nice GUI with copying functionality. flabdablet is right that errors are more likely, but they are still relatively rare, so long as you're using good CDs. With InfraRecorder, you won't be ripping MP3s and burning them; you'll be producing good WAV files and burning them.
posted by koeselitz at 7:20 PM on February 21, 2010 [1 favorite]
The best way is to give her an ISO of the album master, and have her burn it with Imgburn or similar. Extracting audio from a CD accurately is problematic for various reasons -- Exact Audio Copy can do it well, but using it is a bit involved.
If all you have is the CD master, EAC will readily make you a proper ISO for this purpose (I'm pretty sure).
posted by neckro23 at 7:26 PM on February 21, 2010
If all you have is the CD master, EAC will readily make you a proper ISO for this purpose (I'm pretty sure).
posted by neckro23 at 7:26 PM on February 21, 2010
I can recommend CDBurnerXP.
Free and will do exactly what you want it to (bit for bit copy of the cd, not ripping the audio to a computer and reburn)
posted by davey_darling at 7:29 PM on February 21, 2010
Free and will do exactly what you want it to (bit for bit copy of the cd, not ripping the audio to a computer and reburn)
posted by davey_darling at 7:29 PM on February 21, 2010
On further reflection, my answer above is pretty unhelpful. Also, it turns out EAC doesn't make ISOs, but it does make WAV/cuesheets, which can be helpfully burned with Burrrn. So here are some instructions:
1. Install EAC.
2. When you run it, go through the wizard, pick accurate results, and detect drive features with a test CD, or don't. If you put in a reasonably mainstream CD for the test, you'll also be able to set up AccurateRip, which will detect the read offset (basically how far "off" your drive is from the actual audio data), which is usually in the hundredths of seconds so it's not that big of a deal.
3. pick "configure manually" for output encoder, you don't need to set this up unless you're feeling cheeky (see below)
4. pick "I am an expert" because otherwise the ISO option won't show up in the menu.
5. now that you're done configuring, do Action->Test & Copy Image & Create CUE Sheet->Uncompressed (or Compressed with FLAC set up if you're feeling cheeky, Burrrn can handle this), pick a file location/name
6. Wait like an hour! done!
posted by neckro23 at 7:59 PM on February 21, 2010 [1 favorite]
1. Install EAC.
2. When you run it, go through the wizard, pick accurate results, and detect drive features with a test CD, or don't. If you put in a reasonably mainstream CD for the test, you'll also be able to set up AccurateRip, which will detect the read offset (basically how far "off" your drive is from the actual audio data), which is usually in the hundredths of seconds so it's not that big of a deal.
3. pick "configure manually" for output encoder, you don't need to set this up unless you're feeling cheeky (see below)
4. pick "I am an expert" because otherwise the ISO option won't show up in the menu.
5. now that you're done configuring, do Action->Test & Copy Image & Create CUE Sheet->Uncompressed (or Compressed with FLAC set up if you're feeling cheeky, Burrrn can handle this), pick a file location/name
6. Wait like an hour! done!
posted by neckro23 at 7:59 PM on February 21, 2010 [1 favorite]
Nthing the suggestion to make an ISO and have her use imgburn. It's great software.
posted by reptile at 8:19 PM on February 21, 2010
posted by reptile at 8:19 PM on February 21, 2010
One more vote for giving her the ISO/audio files+cuesheet you originally created the CD from. If she isn't going to rip her entire CD collection it's not worth the bother of configuring EAC just for this case; besides, since it appears from your question that it's an original album made by you, there won't be any results for it in the AccurateRip database (unless you have already ripped and uploaded them yourself, but even then I don't know how long it takes until they are accepted).
Also, I'd like to point out that if she goes the EAC route, the ripping process itself (after config is taken care of) can be quite fast if one chooses Test & Copy in Burst mode instead of Secure mode. Still, giving her the audio files and burning them would be the better option, IMHO.
posted by Bangaioh at 12:26 AM on February 22, 2010
Also, I'd like to point out that if she goes the EAC route, the ripping process itself (after config is taken care of) can be quite fast if one chooses Test & Copy in Burst mode instead of Secure mode. Still, giving her the audio files and burning them would be the better option, IMHO.
posted by Bangaioh at 12:26 AM on February 22, 2010
EAC is the only way to go if the original CD has a scratch or scratches on it but it's not the easiest to use. For sheer simplicity, my favorite is Ashampoo Burning Studio Free
You might enjoy looking at this website or other ideas.
posted by luvmywife at 7:16 AM on February 22, 2010
You might enjoy looking at this website or other ideas.
posted by luvmywife at 7:16 AM on February 22, 2010
How many copies is she making? Self-burning gets really tedious, and then what do you do about the disc art? Back in the day, I got bored after doing about 20 copies. <> There are other options, email me via profile if interested. <>
posted by omnidrew at 7:27 AM on February 22, 2010
posted by omnidrew at 7:27 AM on February 22, 2010
Response by poster: OK, a couple of possible solutions listed here, and I will start to explore them.
The Master CD is formatted and set exactly how we want it (conforming to all pro audio standards for a CD master). We will not be ripping the audio and burning a CD that way, the CD we create needs to be an exact duplicate. I will probably explore ImgBurn and CDBurnerXP first, and we will try creating an iso file and burning the disks from that. From what I am reading, that should give us an exact copy, which is what we want.
She has no budget for this album, and it is not going to be commercially released in any way, so that is why she is duplicating them herself. She is going to be making less than 100 copies, and it is something that she can do in the background while cooking/reading/watching TV/etc. All of the CD's have already been lightscribed with the titles, and she printed up all of the artwork already, so at this point the last step is to burn the copies.
posted by markblasco at 10:05 AM on February 22, 2010
The Master CD is formatted and set exactly how we want it (conforming to all pro audio standards for a CD master). We will not be ripping the audio and burning a CD that way, the CD we create needs to be an exact duplicate. I will probably explore ImgBurn and CDBurnerXP first, and we will try creating an iso file and burning the disks from that. From what I am reading, that should give us an exact copy, which is what we want.
She has no budget for this album, and it is not going to be commercially released in any way, so that is why she is duplicating them herself. She is going to be making less than 100 copies, and it is something that she can do in the background while cooking/reading/watching TV/etc. All of the CD's have already been lightscribed with the titles, and she printed up all of the artwork already, so at this point the last step is to burn the copies.
posted by markblasco at 10:05 AM on February 22, 2010
We will not be ripping the audio and burning a CD that way, the CD we create needs to be an exact duplicate.
In general, there is simply no way to guarantee this with consumer grade CD burners. Given that you've got a (presumably clean) master, the chances of good duplication are quite high, but they're certainly not 100%.
The Master CD is formatted and set exactly how we want it (conforming to all pro audio standards for a CD master).
The last step in the production of this fully buzzword compliant master must have involved burning it from an image file (or set of files - perhaps a .bin and a .cue, or a bunch of .wavs and a .cue) on some computer somewhere. Just give her a copy of the same image file(s), and InfraRecorder (or any other program capable of burning a CD from an image) will produce, with a 100% chance of success given good blanks, an exact duplicate of your master CD.
We will not be ripping the audio and burning a CD that way
If you're using any computer-based software capable of copying an audio CD, this is in fact precisely what it will do under the hood. Whether or not it makes actual separate .wav files and a .cue, or whether all that stuff gets put together inside some kind of image file, any program that copies audio CDs must do digital audio extraction to get the data off them.
the CD we create needs to be an exact duplicate.
And the simplest, easiest, least-fuss way to guarantee that is to produce it using the same last step that produced your master: burn it from the same image file(s) used to burn the master.
posted by flabdablet at 6:48 PM on February 22, 2010 [1 favorite]
In general, there is simply no way to guarantee this with consumer grade CD burners. Given that you've got a (presumably clean) master, the chances of good duplication are quite high, but they're certainly not 100%.
The Master CD is formatted and set exactly how we want it (conforming to all pro audio standards for a CD master).
The last step in the production of this fully buzzword compliant master must have involved burning it from an image file (or set of files - perhaps a .bin and a .cue, or a bunch of .wavs and a .cue) on some computer somewhere. Just give her a copy of the same image file(s), and InfraRecorder (or any other program capable of burning a CD from an image) will produce, with a 100% chance of success given good blanks, an exact duplicate of your master CD.
We will not be ripping the audio and burning a CD that way
If you're using any computer-based software capable of copying an audio CD, this is in fact precisely what it will do under the hood. Whether or not it makes actual separate .wav files and a .cue, or whether all that stuff gets put together inside some kind of image file, any program that copies audio CDs must do digital audio extraction to get the data off them.
the CD we create needs to be an exact duplicate.
And the simplest, easiest, least-fuss way to guarantee that is to produce it using the same last step that produced your master: burn it from the same image file(s) used to burn the master.
posted by flabdablet at 6:48 PM on February 22, 2010 [1 favorite]
markblasco: “The Master CD is formatted and set exactly how we want it (conforming to all pro audio standards for a CD master). We will not be ripping the audio and burning a CD that way, the CD we create needs to be an exact duplicate. I will probably explore ImgBurn and CDBurnerXP first, and we will try creating an iso file and burning the disks from that. From what I am reading, that should give us an exact copy, which is what we want.”
flabdablet: “If you're using any computer-based software capable of copying an audio CD, this is in fact precisely what it will do under the hood. Whether or not it makes actual separate .wav files and a .cue, or whether all that stuff gets put together inside some kind of image file, any program that copies audio CDs must do digital audio extraction to get the data off them.”
Indeed. In fact, I'd go even further - not only is any CD copying program going to be 'ripping' the audio to (at the very least) high-quality WAV files right off the bat, but if you're producing a CD master, you're producing a set of synced high-quality WAV files right off the bat. Right?
We can all talk about the best CD ripping methods all day long here, but it seems slightly pointless considering that by ripping the disc we're introducing a potentially error-creating step into the process. The question is: why are you producing copies from a CD in the first place? Why aren't you burning CDs from the original master files? The only thing I can think is that this CD was created using some old-media process that doesn't involve a computer.
But if this album was created using a computer at all, then you should just go to the computer it was made on, get those files, and use the files to burn all the copies. If you can't burn the copies using the specific computer the album was mastered on, you should copy the files to physical media (i.e. a USB drive, or onto a CD as data files) and carry them to a computer where you can – ie her computer.
I know she's got a physical copy of the CD that she likes very much, but trying to copy that CD adds a pointless step to the process. Shouldn't you just be burning all future disks directly from the master files? I guess I just don't understand why you aren't being more direct about burning the disk.
posted by koeselitz at 7:20 PM on February 22, 2010
flabdablet: “If you're using any computer-based software capable of copying an audio CD, this is in fact precisely what it will do under the hood. Whether or not it makes actual separate .wav files and a .cue, or whether all that stuff gets put together inside some kind of image file, any program that copies audio CDs must do digital audio extraction to get the data off them.”
Indeed. In fact, I'd go even further - not only is any CD copying program going to be 'ripping' the audio to (at the very least) high-quality WAV files right off the bat, but if you're producing a CD master, you're producing a set of synced high-quality WAV files right off the bat. Right?
We can all talk about the best CD ripping methods all day long here, but it seems slightly pointless considering that by ripping the disc we're introducing a potentially error-creating step into the process. The question is: why are you producing copies from a CD in the first place? Why aren't you burning CDs from the original master files? The only thing I can think is that this CD was created using some old-media process that doesn't involve a computer.
But if this album was created using a computer at all, then you should just go to the computer it was made on, get those files, and use the files to burn all the copies. If you can't burn the copies using the specific computer the album was mastered on, you should copy the files to physical media (i.e. a USB drive, or onto a CD as data files) and carry them to a computer where you can – ie her computer.
I know she's got a physical copy of the CD that she likes very much, but trying to copy that CD adds a pointless step to the process. Shouldn't you just be burning all future disks directly from the master files? I guess I just don't understand why you aren't being more direct about burning the disk.
posted by koeselitz at 7:20 PM on February 22, 2010
Response by poster: The master was created using CD architect. As far as I can tell, it doesn't create an iso file, at least not one that I can find. All it does it take audio files (which we pre mastered) and burn a redbook CD master. We assembled the files in CD Architect, adjusted all of the spacing and fades between tracks to make sure the album played correctly, and burned the master from there.
As I understand it (and maybe things have changed), taking the audio files and burning them in another program (say itunes, for example) will not give us a redbook CD, and therefor the CD will potentially have compatibility issues.
posted by markblasco at 7:23 PM on February 22, 2010
As I understand it (and maybe things have changed), taking the audio files and burning them in another program (say itunes, for example) will not give us a redbook CD, and therefor the CD will potentially have compatibility issues.
posted by markblasco at 7:23 PM on February 22, 2010
Or, to be more succinct:
It just doesn't make sense to have a 'master CD.' CDs are pretty fragile, as media goes. You should be working with master files.
posted by koeselitz at 7:23 PM on February 22, 2010
It just doesn't make sense to have a 'master CD.' CDs are pretty fragile, as media goes. You should be working with master files.
posted by koeselitz at 7:23 PM on February 22, 2010
Ah - CD Architect. You have your CD saved as a CD Architect Project (.cdp) file, right? Here's what you need to do:
(1) Open your CD Architect project file (.cdp) in CD Architect.
(2) Select Disc -> Burn CD.
(3) When the "Burn Disc-at-Once Audio CD" dialogue appears, use your normal settings, selecting "Burn CDs;" however, make sure to check the "Render temporary image before burning" option first. When you come to the point of actually burning the CD, cancel the process, but leave CD Architect open.
(5) Find the temporary CD Image you've saved and copy it. (This might be difficult; I don't know if CD Architect lets you select a particular file, or if it sticks this in its temp folder. Let me know if you have trouble on this point.) Now you can exit CD Architect; when you do, the original temporary CD Image will be deleted.
(7) Take that .iso and copy it to a USB drive. Carry it to her computer.
(8) Install InfraRecorder (which I prefer; CDBurnerXP never worked very well for me, but YMMV) or ImgBurn and open one of them, setting it to "burn an image," and burn the .iso to as many discs as you like.
I'm gathering all this partially from the CD Architect Manual, by the way.
posted by koeselitz at 7:58 PM on February 22, 2010
(1) Open your CD Architect project file (.cdp) in CD Architect.
(2) Select Disc -> Burn CD.
(3) When the "Burn Disc-at-Once Audio CD" dialogue appears, use your normal settings, selecting "Burn CDs;" however, make sure to check the "Render temporary image before burning" option first. When you come to the point of actually burning the CD, cancel the process, but leave CD Architect open.
(5) Find the temporary CD Image you've saved and copy it. (This might be difficult; I don't know if CD Architect lets you select a particular file, or if it sticks this in its temp folder. Let me know if you have trouble on this point.) Now you can exit CD Architect; when you do, the original temporary CD Image will be deleted.
(7) Take that .iso and copy it to a USB drive. Carry it to her computer.
(8) Install InfraRecorder (which I prefer; CDBurnerXP never worked very well for me, but YMMV) or ImgBurn and open one of them, setting it to "burn an image," and burn the .iso to as many discs as you like.
I'm gathering all this partially from the CD Architect Manual, by the way.
posted by koeselitz at 7:58 PM on February 22, 2010
It won't be making a .iso file, as those are designed to hold images of an ISO9660 filesystem (which an audio CD isn't) for burning to a CD-ROM (which is not a Red Book audio CD). You will probably be looking for a bunch of .wav files (which contain the audio) and a .cue file (which contains the track-to-track timings).
So I've just downloaded the CD Architect manual, and on page 36 of the PDF (whose printed page number is 32) it talks about "Rendering a CD image file". That's what you want to do.
Now, CD Architect's image files are .wav files, but they represent a whole audio CD complete with table of contents, multiple audio tracks, and optional CD text. So assuming Sony hasn't done anything completely outrageously proprietary (not necessarily a safe assumption with Sony), they're probably using features of the full Microsoft RIFF spec for .wav files that allows for all this kind of stuff. Unfortunately, most software that deals with .wav files doesn't use the fully generalized RIFF spec, but a very restricted subset of it; most .wav files are a single audio track, and most audio CD burning software capable of using .wav files will use one for each track plus a .toc or .cue file for the track spacing info.
I'm looking around for more information on CD Architect's image file format. It should be possible to find something that will parse a CD Architect image file and write out its exact equivalent in some other format that common CD burning software understands; once this is found, that other burning software will be able to produce a bit-identical CD to that burned by CD Architect.
Until somebody finds such a conversion tool, then sadly it probably is in fact true that the best you can do is use EAC to extract the best possible rip (bunch of .wav files and a cue sheet) of your master CD, and use those files as sources for your duplication burns. Once you have those files, just about any burner app (including InfraRecorder) can churn out Red Book compliant discs from them.
By the way: Red Book compliance is not a CD Architect special feature. The original Red Book is just the canonical description of the audio CD format. Every burner app that burns discs that you can play in a standard CD player is making Red Book compliant discs, by definition.
posted by flabdablet at 4:14 AM on February 23, 2010 [1 favorite]
So I've just downloaded the CD Architect manual, and on page 36 of the PDF (whose printed page number is 32) it talks about "Rendering a CD image file". That's what you want to do.
Now, CD Architect's image files are .wav files, but they represent a whole audio CD complete with table of contents, multiple audio tracks, and optional CD text. So assuming Sony hasn't done anything completely outrageously proprietary (not necessarily a safe assumption with Sony), they're probably using features of the full Microsoft RIFF spec for .wav files that allows for all this kind of stuff. Unfortunately, most software that deals with .wav files doesn't use the fully generalized RIFF spec, but a very restricted subset of it; most .wav files are a single audio track, and most audio CD burning software capable of using .wav files will use one for each track plus a .toc or .cue file for the track spacing info.
I'm looking around for more information on CD Architect's image file format. It should be possible to find something that will parse a CD Architect image file and write out its exact equivalent in some other format that common CD burning software understands; once this is found, that other burning software will be able to produce a bit-identical CD to that burned by CD Architect.
Until somebody finds such a conversion tool, then sadly it probably is in fact true that the best you can do is use EAC to extract the best possible rip (bunch of .wav files and a cue sheet) of your master CD, and use those files as sources for your duplication burns. Once you have those files, just about any burner app (including InfraRecorder) can churn out Red Book compliant discs from them.
By the way: Red Book compliance is not a CD Architect special feature. The original Red Book is just the canonical description of the audio CD format. Every burner app that burns discs that you can play in a standard CD player is making Red Book compliant discs, by definition.
posted by flabdablet at 4:14 AM on February 23, 2010 [1 favorite]
Yeah, I saw that on page 36 too - but I was confused by the weird fact that it outputs single .wav files as images (ie one single file for an entire disc, not differentiated into tracks I presume). This may well produce a .wav file you can burn to a CD using InfraRecorder or some such, but... well, I feel skeptical that InfraRecorder would take a single .wav file and produce anything but a CD with a single track, right?
This seems odd to me. I think you know more about it than I do, flabdablet. But I'm also beginning to wonder strongly that you might just want to abandon CD Architect for another mastering program. I am doubtful that CD Architect is the only Audio CD program capable of producing a widely-compatible disc.
posted by koeselitz at 4:24 AM on February 23, 2010
This seems odd to me. I think you know more about it than I do, flabdablet. But I'm also beginning to wonder strongly that you might just want to abandon CD Architect for another mastering program. I am doubtful that CD Architect is the only Audio CD program capable of producing a widely-compatible disc.
posted by koeselitz at 4:24 AM on February 23, 2010
It still seems possible - doesn't it? - to simply take the original .wav files that are being fed into CD Architect and just pass them on to her, to let her burn them to disc using InfraRecorder or ImgBurn, right? Wouldn't that work nicely?
posted by koeselitz at 4:26 AM on February 23, 2010
posted by koeselitz at 4:26 AM on February 23, 2010
koeselitz, the full format specification for .wav files is RIFF, which allows for all kinds of things to get wedged in there. If there's a RIFF subchunk specification for whatever it is you want to stuff into a .wav, you can do it.
The fact remains that most .wav files use a tiny subset of full RIFF (header and two subchunks) and it's this restricted format that every CD burning app will expect in .wav files, to my knowledge. I don't know what InfraRecorder would do if you fed it a full-format .wav image output from CD Architect, but I'd be very very surprised if it was the right thing.
As for using the files originally fed into CD Architect and feeding them into something else instead: no, this will not work. CD Architect does timing, sound level etc. processing on its input files (which is kind of the point of using it) that a straight burner is not going to do. Mind you, if none of that has actually been used - if the master CD in question is in fact just a bunch of separate tracks with a default two second inter-track gap - then yes, kicking CD Architect to the kerb and mastering with almost any CD burning app would be the way to go.
I agree that CD Architect's apparent inability to produce a ready-to-burn disc image in a widely supported format makes it a poor choice for CD authoring.
posted by flabdablet at 4:22 PM on February 23, 2010 [1 favorite]
The fact remains that most .wav files use a tiny subset of full RIFF (header and two subchunks) and it's this restricted format that every CD burning app will expect in .wav files, to my knowledge. I don't know what InfraRecorder would do if you fed it a full-format .wav image output from CD Architect, but I'd be very very surprised if it was the right thing.
As for using the files originally fed into CD Architect and feeding them into something else instead: no, this will not work. CD Architect does timing, sound level etc. processing on its input files (which is kind of the point of using it) that a straight burner is not going to do. Mind you, if none of that has actually been used - if the master CD in question is in fact just a bunch of separate tracks with a default two second inter-track gap - then yes, kicking CD Architect to the kerb and mastering with almost any CD burning app would be the way to go.
I agree that CD Architect's apparent inability to produce a ready-to-burn disc image in a widely supported format makes it a poor choice for CD authoring.
posted by flabdablet at 4:22 PM on February 23, 2010 [1 favorite]
Thanks, flabdablet; I think that helps. It helps me, at least. I do a tiny bit of recording on my own, and every little bit of learning is useful.
posted by koeselitz at 4:54 PM on February 23, 2010
posted by koeselitz at 4:54 PM on February 23, 2010
Also, just in case this is not already clear: a CD represents audio as a sequence of 16 bit integer samples, at the rate of 44100 samples per channel per second. When you use something like EAC to rip a CD to a set of .wav files, you get one .wav file per CD track and a cue file that specifies the timing relationship between tracks. Each .wav header will specify that the .wav data are to be interpreted as two channels of 16 bit samples at 44100 samples per second. The .wav data will contain exactly the same sample bits as the original CD. So when you subsequently hand that cue file and that set of .wav files to CD burning software and tell it to make an audio CD, then provided the original rip was error-free, the output disc will in fact contain a table of contents and sample data that are bit-for-bit identical with the original.
It's only when your intermediate audio files are in some lossy compressed format (e.g. MP3) that rip + burn != copy.
You can save some storage space by converting the intermediate .wav files to a lossless compressed format such as FLAC and still end up with a completely faithful copy. Although the FLAC files themselves do not contain the same bits as the original or copy CD, they contain enough information to recreate those exact bits. In other words, the CD -> FLAC encode -> .flac storage -> FLAC decode -> CD process is absolutely bit-for-bit equivalent with and CD -> .wav storage -> CD as far as the end result is concerned.
The main reason you need to jump through all these hoops, instead of just "copying all the bits" from the original CD onto another CD, perhaps through some kind of image file intermediary, is that consumer-grade CD drives simply don't provide a command set for data access at that low a level. The drive firmware will always do some degree of error detection and correction on read, and the error detection codes it uses for that stay inside the drive rather than being exposed via the command interface.
In fact, when reading from a Red Book audio CD, the error "correction" might even be as brutal as using linear interpolation between readable audio samples in order to make up for uncorrectable ones - so a "raw" disc read might return bit patterns that were never written to the disc in the first place. This is why the only way to guarantee that two discs are bit-for-bit identical is to burn them from the same sources.
Similarly, data written to a CD burner will get error correction codes added and bit-twiddling encoding performed before being written; once again, there are simply no commands provided that allow the PC full control over the bit stream actually written to disc.
posted by flabdablet at 2:01 AM on February 24, 2010 [2 favorites]
It's only when your intermediate audio files are in some lossy compressed format (e.g. MP3) that rip + burn != copy.
You can save some storage space by converting the intermediate .wav files to a lossless compressed format such as FLAC and still end up with a completely faithful copy. Although the FLAC files themselves do not contain the same bits as the original or copy CD, they contain enough information to recreate those exact bits. In other words, the CD -> FLAC encode -> .flac storage -> FLAC decode -> CD process is absolutely bit-for-bit equivalent with and CD -> .wav storage -> CD as far as the end result is concerned.
The main reason you need to jump through all these hoops, instead of just "copying all the bits" from the original CD onto another CD, perhaps through some kind of image file intermediary, is that consumer-grade CD drives simply don't provide a command set for data access at that low a level. The drive firmware will always do some degree of error detection and correction on read, and the error detection codes it uses for that stay inside the drive rather than being exposed via the command interface.
In fact, when reading from a Red Book audio CD, the error "correction" might even be as brutal as using linear interpolation between readable audio samples in order to make up for uncorrectable ones - so a "raw" disc read might return bit patterns that were never written to the disc in the first place. This is why the only way to guarantee that two discs are bit-for-bit identical is to burn them from the same sources.
Similarly, data written to a CD burner will get error correction codes added and bit-twiddling encoding performed before being written; once again, there are simply no commands provided that allow the PC full control over the bit stream actually written to disc.
posted by flabdablet at 2:01 AM on February 24, 2010 [2 favorites]
More arithmetic: 44100 16-bit samples per second on two channels is 176400 bytes per second, and this is the standard (1X) CD data read rate. The drive handles samples in blocks, at 75 blocks per second. 176400 bytes per second / 75 blocks per second = 2352 bytes per block.
The lowest level of data access that a consumer CD-ROM drive provides to a PC ("raw mode") allows it to read or burn data in 2352-byte blocks. But behind the scenes, each block is represented on disc as 98 frames, each containing 24 of the data bytes (three stereo samples if the data are Red Book audio) along with a control byte (whose bits are referred to as "sub-channels" P through W) and eight error-correction bytes, for a total of 3234 bytes per on-disc block. None of the extra stuff ever makes it to the outside of the drive; it's used for data location and error checking on read, and regenerated on burn. You specify a "write mode" for any given write operation that indirectly controls what the drive will put in the sub-channel bits. The Table of Contents is encoded in the Q sub-channel bits within the lead-in track (whose 2352 data bytes per block are unused), and the drive provides specific commands to read and write a TOC.
CD-ROM tracks come in three flavours (Mode 0, Mode 1, Mode 2) all of which have different Q-channel encodings and data byte layouts, and none of which have the same Q-channel encoding as a CD audio track. ISO image files get burned as Mode 1 (CD-ROM Data) tracks, which is why you can't store a CD audio image in an ISO file. Mode 1 data ships in 2048-byte blocks, to each of which the drive internally adds addressing and error-correction fields to bring it up to 2352 data bytes. These are then split into 98 frames and more stuff added to each frame just as in raw mode. Yes, it really does take three levels of error correction to make CD-ROMs acceptably reliable.
Red Book audio tracks only have the two levels of error correction built into the block's 98 frames, and only P and Q channel information for block addressing, and that's why they're nowhere near as reliably or reproducibly readable as CD-ROM tracks.
Here are even more of the gory details for those interested.
posted by flabdablet at 3:59 AM on February 24, 2010
The lowest level of data access that a consumer CD-ROM drive provides to a PC ("raw mode") allows it to read or burn data in 2352-byte blocks. But behind the scenes, each block is represented on disc as 98 frames, each containing 24 of the data bytes (three stereo samples if the data are Red Book audio) along with a control byte (whose bits are referred to as "sub-channels" P through W) and eight error-correction bytes, for a total of 3234 bytes per on-disc block. None of the extra stuff ever makes it to the outside of the drive; it's used for data location and error checking on read, and regenerated on burn. You specify a "write mode" for any given write operation that indirectly controls what the drive will put in the sub-channel bits. The Table of Contents is encoded in the Q sub-channel bits within the lead-in track (whose 2352 data bytes per block are unused), and the drive provides specific commands to read and write a TOC.
CD-ROM tracks come in three flavours (Mode 0, Mode 1, Mode 2) all of which have different Q-channel encodings and data byte layouts, and none of which have the same Q-channel encoding as a CD audio track. ISO image files get burned as Mode 1 (CD-ROM Data) tracks, which is why you can't store a CD audio image in an ISO file. Mode 1 data ships in 2048-byte blocks, to each of which the drive internally adds addressing and error-correction fields to bring it up to 2352 data bytes. These are then split into 98 frames and more stuff added to each frame just as in raw mode. Yes, it really does take three levels of error correction to make CD-ROMs acceptably reliable.
Red Book audio tracks only have the two levels of error correction built into the block's 98 frames, and only P and Q channel information for block addressing, and that's why they're nowhere near as reliably or reproducibly readable as CD-ROM tracks.
Here are even more of the gory details for those interested.
posted by flabdablet at 3:59 AM on February 24, 2010
tl;dr: The collection of .wav files and the cue file that you get from an error-free rip of an audio CD are the closest you will ever get to a bit-for-bit equivalent of what's encoded on that CD, and burning another CD from those is as close as you will ever get to performing a bit-for-bit copy. But there's no absolute guarantee, even with a really good ripper like EAC, that an audio CD rip is 100% error-free.
Your ears can tell you things that CD ripping software can't. Listen carefully to your ripped .wav files before committing to a production run based on them.
posted by flabdablet at 4:12 AM on February 24, 2010
Your ears can tell you things that CD ripping software can't. Listen carefully to your ripped .wav files before committing to a production run based on them.
posted by flabdablet at 4:12 AM on February 24, 2010
Response by poster: Wow, this got a little crazy! I have been using CD Architect for years, and several duplication houses have told me to use that program to create the master CD's for them, so that has always been the way I do it, and to NOT use just any CD burning software. I never realized just copying a CD was so difficult.
We ended up using ImgBurn, ripped an image of the disk, verified that image against the master disk, and she is using that to make the copies. So far everything seems to be working great.
posted by markblasco at 10:55 PM on February 25, 2010
We ended up using ImgBurn, ripped an image of the disk, verified that image against the master disk, and she is using that to make the copies. So far everything seems to be working great.
posted by markblasco at 10:55 PM on February 25, 2010
This thread is closed to new comments.
posted by anthropomorphic at 6:50 PM on February 21, 2010 [1 favorite]