Why can't CD's contain more than 80 minutes if the files total less than 700mb?

[Tornado]

I've always wondered this since I started burning CDs as .wav, but why is it that when you burn an mp3 CD it won't let you have more music space than if you burn a .wav CD? If the mp3 is smaller by such a wide margin than the equivalent .wav file, you can burn hundred of mp3s to a CD when they aren't playable in CD players but a .wav takes up about as much space as it does when it is playable on CD players.

 

[daan]

An audio CD gets converted to audio so that it can be played on a normal CD player. The original file type makes no difference.

Example: An audio track can be a 4mb mp3 or a 40mb wav file, but it still plays for 4 minutes irrespective of it's type.

 

[Tornado]

So audio CDs are only measured by time, so long as they don't exceed 700mb?

 

[daan]

Its 2 different file storage systems. An audio CD is like an LP record and is limited by time, a data CD is like a hard disk and is limited by size.

Stick an audio CD in your PC, and there is nothing on it. Used space was 0 bytes on the one I just tried (even though there were 18 .cda tracks at 44bytes each).

 

[Empty_One]

The audio format used by CD's, CDDA (Compact Disc Digital Audio), is not compressed, while mp3's are. 80 minutes of CD audio take up 700 MB.

 

[Dave A]

Not quite, I have audio CD's that are cose to the 80 minute mark and some are no more than 500MB in size but the CD still can't have more than 80 minutes of music on it. It's not about the data size on an Audio CD, ofcourse the CD itself is still limited in size but it's about the method of reading that data. Daan has the analogy with LP's covered.

 

[wfooshee]

There is also the question of burning a CD-ROM containing MP3 files, rather than an actual audio CD. Most of the newer players, especially car players, play these just fine, and you can have a relatively huge library on a single disc. But if you burn MP3s to an audio CD, they get converted back to the standard audio CD format, so they're back to an uncompressed full size file. And as stated, that format is time-limited, not size-limited.

 

[ROAD_DOGG33J]

They can contain more than 80 minutes, if you burn it as a data CD. The reason why you couldn't get above 80 minutes with MP3's is because they were converted to Red Book format so they could be played on a normal CD player. WAV files are close to what is stored on a CD.

 

[wfooshee]

They can contain more than 80 minutes, if you burn it as a data CD.

I think I just said that. . . .

 

[Thiele]

Audio CD's aren't sorted by time, but if when the music is converted, it has roughly 11mb per minute, so 80 minutes = 700mb.

Edit: i just read up

 

[Doggie]

Interesting trivia that most of you propably allready know is the lenght of the normal CD. Where did the 74min lenght come from?

For those of you that don´t know, here's the link:
http://en.wikipedia.org/wiki/Compact_Disc#Storage_capacity_and_playing_time

 

[Sureboss]

Its 2 different file storage systems. An audio CD is like an LP record and is limited by time, a data CD is like a hard disk and is limited by size.

Stick an audio CD in your PC, and there is nothing on it. Used space was 0 bytes on the one I just tried (even though there were 18 .cda tracks at 44bytes each).

That's shocking.

They have CDs in Scotland! I suppose you need something to chop up crack on though