Mp3 confusion!

[Stace]

Hello all. I'd really appreciate it if someone could clarify something for me: I understand how the Mp3 audio format can reduce file sizes which increases the number of songs you can burn to a CDR. But discs are limited not only to a maximum number of MB they can hold, but also a total time---around 80 minutes. I can see how people burn 150 Mp3s to a CDR and only take up 666 MB total, but those songs also total 12 hours in time----how do they get 12 hours of music on an 80-minute disc? My enquiring mind would like to know!
Thanks!
Stace

[neuroking]

Easy. The CDs burnt with MP3 files only play in "MP3 compatible" CD players, which can read and decode those files. Regular CD players only read/decode standard CD audio 'files' (tracks), which means no compression, and therefore only 80 minutes.

80 minutes actually in CD-Audio format = ~700MB.
12hrs in MP3 format = ~700MB.

Only catch is that you have to have a CD player that plays it (CD players advertising CD-R compatibility don't necessarily play MP3 CDs. They are just better able to overlook inconsistencies more prevalent in CD-R media versusprofessionally master CDs)

[ECA]

MP3 format is a DATA format...NOT just an Audio format.

a CD has 2 formats that can be written to it.
FULL audio, which is 70 min...
DATA which is 700MB..

the computer SEE's MP3, as a Music/sound format, but it has to be in a data format to play...ABIt confusing, but computers CANT read ANALOG properly, with out ALOT of extra hardware. So it converts your CD into DATA format called MP3/WMA/Whatever.. to record it. the BITRATE, is what is most important.
HIGHER Bitrate, better sound(most times), ALSO equals LARGER size, and more room to store it.
ALSO, if useing a player that can ONLY play at a CERTAIN bitrate...128bps, with MP3 at 320bps...CAN be a waste of time.. BUT, as for stoeing them AWAY, in the best format...A HIGHER bitrate is better, becasue it TRYS to keep EVERYTHING...and can be changed to a LOWER bitrate...Where a LOW bitrate MP3, CANT be raised to ADD more sound/quality..

[Stace]

Thanks neuroking & ECA. If I understand it, the max amount of music that can be burned to a CDR is based on the music's total megabytes OR its total time, and you worry about one or the other based on whether you are encoding the CDR as an audio or data disc.

Mp3 is always encoded as a data disc so you can cram as much music as you want on the disc as long as it's under 700MB.

A disc with only AIFF or WAV files would be an audio disc and the limitation would be the 80 minutes. But I'm not sure I have that right because iTunes claims to burn 185 AAC files to a single disc: the total time for 185 audio files would be about 600 minutes and the max time for an audio disc is 80 minutes.

Also, does one buy a separate audio disc and a separate data disc, or do you use the same disc and just encode it one way or the other?

Your responses are very appreciated!
STACE

[Ioman]

Hi Stace,

When a disc says 700MB or 80min, that refers to 700mb as a data metric and when it says 80min, this refers to 700mb of uncompressed audio in the original CD-Audio format. Putting MP3's onto a CD and leaving them in MP3 format, nulls that 80min number because obviously you can put hours of MP3 audio on a CD. You just need a CD player that can read the MP3's in their native format.

Regular CD Audio is not in the AIF or WAV format, its in CDA (http://www.coolutils.com/Formats/CDA) format. And that 80min only refers to that format.

[ECA]

NOW,
Want something COMPLETELY confusing??
EVEN AUDIO can be cut down. With the right progs. You can change the Audio and shorten it. This can let you ADd more to it..AT the loss of Quality.

WE REALLy dont want an audiophile to see this...

AND, IF you REALLy like Audio and you record your OWN and DUB it out, you can use 1 CD and probably NEVEr get 80min...