Let’s say I have an original CD, and I decide to rip the tracks to 128kbps. I later burn those tracks to a blank CD. How is the audio treated now if I decide to rip the copy? If I do it at 128kbps again, will the new files be identical to the old ones? If I do it at 320kbps or even lossless, will these new files be larger while having no difference in quality? Can software recognize CD’s quality?
Once you ripped the CD the first time, you have irretrievably lost information due to the lossy compression applied by the MP3 encoding. When you then burn those files to a new CD, the new CD will replicate that loss of quality.
Ripping the new CD again means putting the already-compressed audio through the compressor again, meaning you will lose even more information. If you rip it lossless, then the result should be nominally similar to what’s on the CD, but not necessarily the same, since the files has gone through many format conversions.
mp3 is a lossy compression scheme, and so you will lose quality every time you use it.
So when you rip the CD again you will also lose yet more information when you encode to mp3 and your new mp3 files will sound slightly worse. This is true even if you went and ripped them at 256 kbps. In that case you’d end up with a larger file that sounds slightly worse than your original 128 kbps one.
a minute too late I see.
Well, the statement that information is lost is true.
However - the statement that “it will sound worse” is not necessarily true.
For some types of music and with properly high quality MP3 encoding settings the output file may be audibly transparent to the original. This is because human ears don’t read bits, they interpret sound. If you rip a CD, encode with super high quality settings, reburn as audio and then rerip the outcome may well be audibly transparent to the original.
A few years back I was really into playing with MP3 encoding. There are plenty of freeware blind testing programs on the web - i.e., you feed it an uncompressed sample and the compressed sample, and it then quizzes you on which is the original. There are plenty of MP3 settings where I guessed no better than random. And I have pretty good ears.
…of course, if you are worried about the information loss (and I am) I suggest backing up with Monkey’s Audio. It’s a nifty little freeware program that does lossless compression. Of course, it can’t get anywhere near the file compression rates of MP3, OGG, AAC, etc.
Another good lossless audio compression scheme is FLAC. This has the advantage of being integrated into a number of software audio players and many mp3 players themselves (see link for more info).
Kind of off topic but a great audio ripper is
“Exact Audio Copy” which rips from data only on the CD. It takes a lot longer to rip a track although. Sometimes it can get a track to rip if there is a scratch in the CD.
You can download it free from Snapfiles
I have read a lot of people rip their CDs to waves then convert them. But I reckon that is why you got the original CD
Yes. Exact Audio Copy is so good. You should never use anything else. But get it from EAC Homepage