Reasons for keeping full CD rips
Maybe you think: I ripped some CDs to my computer and then converted them to lossy 320kbps mp3. If I discover duplicate songs, fine - I go delete the one that is worse. Saves me disk space.
It depends on what you want, but there are reasons for keeping lossless audio data and resons for keeping full CDs.
what is a full CD rip
A full CD rip (also known as a CD image) is an almost complete copy of the CD's digital data which if burned on to a blank CD would creates a clone of the orginal CD. It includes not just the track audio of a normal rip ("track rip"), but also
- any hidden track (reachable on most CD players by stepping back from track 1)
- any inter-track audio (usually but not always silence)
- any text (known as CD-TEXT) such as album and track titles and artists
- any additional non-audio data such as ISRC and UPC/EAN (barcode number)
The format of CD image disc file is proprietary to the program that made it, e.g. NRG for the Nero program. A clone made by burning such an image will differ in small respects, such as in the CD medium manufacturer information.
why full CD rips
If you deleted the other versions of the song you have no chance to re-check. You also cannot participate very well in discussions of the deleted file with other people.
Additionally you may have problems using cool features, like automatic mass tagging - because the CD in its entirety has gone, the album cannot be recognised by certain software. And some tools currently need full CDs to allow mass tagging.
solution
- maintain a separate archive for your tracks that you think are the best versions of a song
- there may come up tools that can generate best-of-extractions based on the data you have
- e.g. several people gather and create a best-of-text-file. You just get the file, a program looks at what you have, and in the extraction it leaves out duplicates that have a better counterpart.