Burning a CD: Audio CD - this is a typical audio CD that will play in pretty much any music CD player. The gap is the space between tracks, and can be set to whatever you choose. A typical gap would be about 2 seconds. If your songs average four minutes each, you should be able to burn about 19-20 of them on a typical 80 minute CD. Songs that are in iTunes as MP3 or AAC will be re-encoded to AAIF format before burning to CD. Tracks from a standard audio CD would be converted from AIFF to AAC or MP3 (depending on your settings) upon import into iTunes.
Sound check is an option that will compare volume level of each track and make them all about the same. In other words, you won't have to crank up the volume to hear track 1, only to have your eardrums blown out when track 2 starts. MP3 CD - This is basically a data disk with nothing but MP3s on it. Some newer stereos will play MP3 disks. This format allows you to burn many songs on a single CD for either playback on a computer or on a newer CD player with MP3 capability. This is not meant for most standard audio CD players. Data CD or DVD - this is used to archive your library to CD or DVD in case of a system crash. This is not meant for playback. You can find out what format a track is in by clicking on it to highlight it and then either selecting Get Info under the Find menu, or using Command-i to get info. The info window will tell you the format of the song, the bitrate, frequency, and, if available, album art. Bryan On Jan 24, 2005, at 11:47 PM, Marta Edie wrote: > Thanks Bryan, this day was surely a great learning experience for me, > and i am not quite sure how i shall process it all, but I shall have > recourse to the stuff and that is a help. - No. I am not finished > with my questions as yet. When i open the iTunes preferences and > click on burning, I have two options : it says : preferred speed - > then Audio CD, then MP# 3 CD and sound check in between and then > comes Data CD or DVD and that tells me that this might not play on all > players. Now: if I click the audio CD ( being AAC standard if it is > music I bought from the music store, and AIFF if I imported it myself > if that is the standard Apple uses in outside the music store bought > CDs because it would not embed the DRM?) I can have a gap between the > songs which apparently I cannot have if I choose the MP# format, the > songs running together in that format without a pause. Am I correct > here? And what does it do when I check "sound check" ? Who checks what > sound and how do I know according to which criteria the sound is > checked? > Of course when I import now I have the possibility to choose the > format which I did not know a year ago, so I actually cannot tell > anymore now what format all my songs and operas etc were imported in, > because as a fledgling I knew little about the preferences and would > not have known even if I opened the preference panel. > To repeat : if I check the output as Audio CD, will my CD then be > in the AIFF format unless I choose the MP3 format ? Is there a way to > check the format a CD is in at all? By trial and error - meaning > taking it to a player somewhere and see whether it plays? Or something > more professional? > Marta > On Jan 24, 2005, at 20:18, Bryan Forrest wrote: > >> Ok, I know others have already answered this, but I spent a good 20 >> minutes working on it earlier, and I'm gonna send it anyway... so >> there! :-p >> >> >> >> The AIFF (Audio Interchange File Format) is the default format Apple >> uses to read audio files from regular music CDs, i.e., the kind you >> would play in your stereo. These files typically run about 10-12MB >> per minute of audio. So a typical 3.5 minute song would be about >> 35-40MB. >> >> MP3 (Mpeg Layer 3) is the most common form of audio file on the >> internet. The MP3 compression algorithm allows the 35-40MB AIFF (or >> WAV for Windows) file to be compressed to about 1/10th its original >> size (allowing for standard settings of 44.1Khz/128Kbps). >> >> Apple's current standard is AAC (Advanced Audio Codec). This is the >> format that is sold via the iTunes Music Store. It provides higher >> quality audio than MP3 at approximately the same size. In addition, >> Apple is able to embed its DRM, or Digital Rights Management, key >> into each audio track, to prevent unauthorized copying of purchased >> music. AAC currently will only play on iPods and iTunes. >> >> One thing to keep in mind is that both MP3 and AAC are considered >> lossy formats, meaning data is lost in translation. It's not likely >> you will hear the difference unless you have a very well trained ear, >> but it's good to keep in mind. Let's say you have a song on a music >> CD you want to add to your iTunes library. You import the song as an >> AAC file. You probably would have a hard time telling which is the >> original CD and which is AAC, even if you played them both side by >> side. But if you were to burn the AAC back to an audio CD, the data >> that was originally lost in translation to AAC is still gone. It's >> not going to miraculously reappear just because you're converting it >> back to its original format. Then if you play the two CDs side by >> side, you might be more likely to hear the difference, even though >> the difference would be very small. >> >> Data loss can be reduced by using a higher bitrate (128Kbps is >> standard) and a higher frequency (44.1Khz is standard). By default, >> when I import a CD, I use the AAC codec, since I only use iTunes and >> my iPod, and I use a bitrate of 160Kbps with a frequency of 48Khz. >> This increases the size of the files by maybe 33%, but they sound >> much better than using the standard settings. So instead of a file >> being 3.5MB, it might be 5MB. Not a huge difference with today's hard >> drives. If I used a 3rd party MP3 player, I would probably use MP3 at >> 192Kbps and 48Khz. Again, files would be about 50% larger than if I >> had used the default settings. >> >> Hope this helps! >> >> Bryan C. Forrest >> Macintosh Specialist >> LifeNet >> http://www.lifenet.org >> >> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: text/enriched Size: 6035 bytes Desc: not available Url : http://www.math.louisville.edu/pipermail/macgroup/attachments/20050125/d3f5e738/attachment.bin
