I noted above that "one of the CDA files is only 2 KB, while the corresponding MP3 file is 9.25 MB." Then, I asked about the possibility of burning the CDA files in such a manner that qualitatively they are the equivalent of the MP3 files. If possible, then would the CDA files be much larger? How much larger? From what you say, would they be about 4 times as large?

I have to wonder why anyone would really care if they could get only 15 versus 40 tunes on a CD--given that the quality is no different. To me, the issue is not how many decent quality tunes I can get on a CD, but, rather, it is can I put tunes from different CDs on a CD with quality at least as good as MP3. Please explain to a non-MP3er what the issues are.

had to get up to see a patient so thought I'd check out the site again and saw this post and had to respond

mp3 is a way to shrink the files down in size - if you shrink the files down to 128 bits ( the smallest mp3 will allow) then you can several hundred songs on a cd
I could not get 128 to work and had to use 192 and each song averages 4mb - and you can get 70 mb on a cd so I got well over a hundred songs on the cd
with mp3 you can also store in files
for example I made a beatles file and put my favorite 40 beatles songs in it and another file for guns and roses
you could also makes a beatles file and the a subfile withe each album separatley - it also displays the artist name and song title
and there is a random function(I think have not verified yet) that you can just put in the mp3 cd and it will randomly play the songs on the cd

not sure what cda is but if you burn a regular cd it is in minutes and you can only get about 74 minutes on a cd

the mp3 quality is worse than regular cd quality, but I can not tell - but the regualr US stereo also sounds good to me

That is why the ipod is supposedly so good - it shinks the files down to almost mp3 size but the sound quality is supposedly better, but again my ear hears no difference.

Right, good info. Have a great trip, and, as said, be careful. We don't want to have an "incident" report from you when you get back.

I noted above that "one of the CDA files is only 2 KB, while the corresponding MP3 file is 9.25 MB." Then, I asked about the possibility of burning the CDA files in such a manner that qualitatively they are the equivalent of the MP3 files. If possible, then would the CDA files be much larger? How much larger? From what you say, would they be about 4 times as large?

I have to wonder why anyone would really care if they could get only 15 versus 40 tunes on a CD--given that the quality is no different. To me, the issue is not how many decent quality tunes I can get on a CD, but, rather, it is can I put tunes from different CDs on a CD with quality at least as good as MP3. Please explain to a non-MP3er what the issues are.
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The compression between CD Digital Audio and a typical MP3 is actually more like 10 times. The reason you see the .cda file as being only 2KB is because of the way the OS displays CD Digital Audio files (merely as "references" to the real content; this is because a CD audio disc isn't a data CD, but Windows, for example, will "display" the tracks as if they are actual data "files", even though they aren't). A typical track on a CD is around 40-50MB while an MP3 is 3-4MB.

So it's not 15 vs 40. Its more like 15 vs 150-200, depending on the bitrate used.

The compression between CD Digital Audio and a typical MP3 is actually more like 10 times. The reason you see the .cda file as being only 2KB is because of the way the OS displays CD Digital Audio files (merely as "references" to the real content; this is because a CD audio disc isn't a data CD, but Windows, for example, will "display" the tracks as if they are actual data "files", even though they aren't). A typical track on a CD is around 40-50MB while an MP3 is 3-4MB.

So it's not 15 vs 40. Its more like 15 vs 150-200, depending on the bitrate used.
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Thanks das. Your reply totally clarifies what I wanted to know except about the quality issue. Is there any reason at all to think that MP3's would be of higher quality than CDA's--if ripped as WAV files in the first place? If not, then it would appear that the only advantage of being able to play MP3's is because one can get more files on a CD. To me, the higher quality of WAV CDA's, if true, would far outweigh the capacity advantage of MP3's. And, when I talk about quality, I am not talking about perceived quality, I am talking about the absence of information loss.

In thinking about these issues, what would the qualitative difference be if the ripping was to MP3's in the first place and MP3 CDA's were produced? No qualitative difference I presume??? I ran across an interesting read on perceptions concerning MP3's, Pro MP3's, and anther format--which I can't remember the name of now. I'll post a link if I can find the read again.

As I said above, you'll be very hard pressed to distinguish a CD from a high quality MP3 played in a car.

If you ripped a CD and created MP3 files, then burned a CD with those files and uncompressed them to CDA, the resulting CD sound would not be as pristine as the original CD, since most compression algorithms are "lossy" meaning that in the compression process, data is discarded, so even after being uncompressed, the file has lost some data.

You might want to search here to learn more about this:
http://www.wikipedia.org/

When you rip from a CD and create an MP3 file, the software compresses the file, and depending on the bit rate of the resulting file, the sound quality will differ. An MP3 file, since it's compressed, will theoretically have lesser sound quality than a CDA file (which is uncompressed). If you use high quality ripping/encoding software and a reasonably high bit rate (I use Exact Audio Quality w/ LAME encoder @ 256kbps VBR & then normalize with MP3Gain), the resulting MP3 files can be very close to CD quality, especially if you're going to play them in a car (which is a suboptimal audio environment). The sound quality of the MP3s I play on my iPod in the car is so close to CD quality, than even an audiophile would be hard pressed to tell the difference while driving.

Here's EAC/LAME info:
http://users.pandora.be/satcp/tutorials.htm

Here's MP3Gain info:
http://mp3gain.sourceforge.net/

The advantage of MP3s is file compression and therefore ability to hold more music on a given amount of storage space.

If you ripped a CD and created MP3 files, then burned a CD with those files and uncompressed them to CDA, the resulting CD sound would not be as pristine as the original CD, since most compression algorithms are "lossy" meaning that in the compression process, data is discarded, so even after being uncompressed, the file has lost some data.

You might want to search here to learn more about this:
http://www.wikipedia.org/
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Thanks very much Stream. All that you say helps a great deal. At this point, since my car can't play MP3's after all, I will be burning only CDA disks--where the only point is allowing creation of my own "playlists." In this regard, from what you say, I won't be starting from MP3's. If I truly want quality (no information loss) as high as that as on the original CDs (might also be playing them on home audio--not just in car), then how would I proceed. My best attempt, I think, so far has been to RIP using Windows Media Player's lossless format. But, I think that this format still employs some compression???? So, is there a better starting point? And, are the audio files created using the process I described WAV files. They are identified simply as Windows Media Audio Files on my computer. Thanks much again for your thoughts/help.

It is amazing how can we all be investing so much time trying to sort out what our cars will be able to do or not...
It had to be a software issue... :whistle:

So, as a software engineer, i know that the answer is really simple as long as we talk to the right guys: the ones who do the damn system. Who are they? Not "BMW guys" for sure that you can reach using our so knowledgeless dealers...
Any clues? Iceman? I will do some investigation on the net...

Whatever you can find out would be greatly appreciated I am sure. I just wonder if the issue is purely software, or as das suggested, partly hardware too. I am hoping for the former. While CDA's are fine with me, it would be nice to utilize the storage capacity allow my MP3's sometimes.

Whatever you can find out would be greatly appreciated I am sure. I just wonder if the issue is purely software, or as das suggested, partly hardware too. I am hoping for the former. While CDA's are fine with me, it would be nice to utilize the storage capacity allow my MP3's sometimes.
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I know it is not only software. But the guys that build it know the dependencies on the hardware and software versions (or CIP versions). And they also know the meaning of the versions described in the "secret menu".