iTunes tells me there's not enough room when I try to burn my 690 MB playlist to MP3 CD?

I don't have a definitive answer, but my hunch is that it revolves around block sizes and the number of files. Each file requires one or more blocks for storage. Any unused space in a block is lost. The more files there are comprising a playlist that is shy of the 700 MB upper bound the more space will be lost due to incomplete blocks. In Windows Explorer, for example, you can select properties for a bunch of files and get two numbers, size, and size on disk. Block size on CD may be different from local storage, but size on disk should be a better indicator of what would fit than the size in the iTunes status bar. Of course your files won't all be in one place, so you would have to copy them out to a folder to check. A useful exercise once perhaps, but picking a slightly smaller expected capacity and/or switching to larger discs seems to be good advice from the fiend.

tt2

TheRewster1106 wrote:

I'm not interested in arguing semantics whether the manufacturer "lied" or whatever. I just want to remove the guesswork with burning MP3 CDs moving forward.

Then you shouldn't have mentioned it. I simply responded to something that you offered as fact, which it isn't.

As for removing the guesswork; again as stated, it's unlikely that anyone here would have sufficient knowledge to provide you with anything other than their own experienced, but amateur opinion. Perhaps you might find an authoritative answer by asking the disc manufacturers.

In the meantime, since you're using the discs as data CDs (the data being audio in MP3 form) rather than Audio CDs*, perhaps you could try an 800MB disc. Alternatively, make your playlists smaller than 690MB, thereby allowing for any variation in the capacity of an individual disc.

* An Audio CD is one burnt to the industry standard for an Audio CD, i.e. a factory-produced audio CD (which could contain either speech or music), but in a specific file format. A CD with MP3s on it is a data CD that has audio files on it and as such, it may not be playable on some audio CD players since it doesn't conform to the Audio CD standard.

TheRewster1106 wrote:

Google reveals no answers to this question except for the standard "Data discs can hold up to 700 MB" blah blah blah, which is of course a lie; the limit is around 690-ish. But I don't want an -ish.

But 690MB is within the "up to 700MB" limit, so it's not a lie at all. The probably answer is that the capacity of a recordable disc will depend on the error rate incurred when the disc was manufactured. In other words, it's inevitable that every disc will have manufacturing imperfections which mean that the absolute capacity is never exact.

I'm doing an extensive musical project with lots of discs, and I want a firm, exact threshold.

I doubt that anyone here is an expert on the subject.

You're welcome. 🙂

tt2