Play Time vs Bit Rate vs File Size

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riverboatsam
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Play Time vs Bit Rate vs File Size

Post by riverboatsam » Mon Oct 05, 2009 3:24 pm

Hello! I captured a long concert over the internet and went to burn it (using MS Win Media Player) onto CD's. When I split it roughly in half, I get a "10 minutes over" on the 2nd CD. I do NOT want to go to 3 CD's. Now, the recording was made at a very high bitrate. I used Audacity 1.3 to cut the bitrate in half, and sure enough, the file sizes are WAY down. HOWEVER, when I go back to MS Win Media player <even changing to the same lower bitrate as the new copy> I STILL get a "10 minutes over" warning msg on the 2nd CD.
Is it a matter of "you only have 80 minutes per CD" no matter what the bitrate/filesize is? Or is Win Media Player (vers 11) just ..um.... not very intelligent? It doesn't look like Audacity has a "burn" capability.
Has anybody else run into this problem? Does anyone have some suggestions as to what I could do?
thanks in advance,
- RiverboatSam -

waxcylinder
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Re: Play Time vs Bit Rate vs File Size

Post by waxcylinder » Mon Oct 05, 2009 3:42 pm

riverboatsam wrote: Is it a matter of "you only have 80 minutes per CD" no matter what the bitrate/filesize is?
Basically yes - whenyou burn a music CD (as opposed t a data CD) you need to provide 44.1kHz 16-bit PCM stereo with a maximum of 74 minutes (or 80 minutes for later CD-Rs) - This is the Red Book standard for CDs. Some CD burning s/w can take compressed audio and convert back up to the format required for burning a music CD - but note that the compression damage will remain.

You can burn data CDs or (even DVDs if you want greater capacity) with compressed music files on them, MP3s for example. But note that not all CD players can play such disks.

WC
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riverboatsam
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Re: Play Time vs Bit Rate vs File Size

Post by riverboatsam » Mon Oct 05, 2009 5:13 pm

Thank you for your response (unwelcome as the information turned out to be!) :-)
I'm wanting to play the CD in my home audio CD player and my Car CD Player.
I am still having trouble understanding this - when I rip music from a CD, I am ripping it (again, via MS Win Media Player) at 320 Kbps, which, if I understand correctly is way LOWER than what the "CD Company" has recorded it at. It sounds like when I select "Audio CD" to WRITE with - no matter what bit rate I select (192 highest, or perhaps even something LOWER), I GET 128 kBPS (44.1 Khz.) (??)
I can make an exact copy of a CD from my home collection (I think they use the .CDA suffix?). So I don't believe it's a case of "Superior Professional recording and/or CD capability."
If my player in the home/car can play the MUCH higher rate a professional CD is recorded at, then why wouldn't it be able to play the much lower rate that I can record on an MP3 - WITH more time on the CD? Maybe the encoding method? (My MP3 player will play SOME .WMA songs, but not others... so I'll allow there IS weirdness out there with these methods).
(Oh, BTW - some of these questions are, perhaps, rhetorical.)
I suppose I can try making these "data disks," but I'm pretty sure my system(s) will only play "audio" type disks that have been "finalized" <no further updates can occur>
The whole thing just seems bizarre.

waxcylinder
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Re: Play Time vs Bit Rate vs File Size

Post by waxcylinder » Mon Oct 05, 2009 5:48 pm

riverboatsam wrote: If my player in the home/car can play the MUCH higher rate a professional CD is recorded at, then why wouldn't it be able to play the much lower rate that I can record on an MP3 - WITH more time on the CD? Maybe the encoding method?
Well yes, it's because on a professional CD or a music CD that you burn from WAV files these files are created to the format that CDs use - similar to WAV in that it is a lossless format - but different in that there isn't really a set of files on the CD but rather a stream of digital data and a TOC (Table Of Contents) that tells the CD player where each "track" starts (so it's not like an LP where you can see the inter-track gaps).

I would try making a data CD with your MP3s on and then test it in each of the players you want to play it in - you may luck-out and get it to play in all of them (it wouldn't work for me in any of my players) - otherwise you will have to stick with music CDs and be stuck with the 80 minutes max.

And your'e right about needing an MP3 Codec (actually only the dec part - the decoder) in the CD player for playing MP3s - which is precisely why not all cd players will play such disks - as they don't all contain such a codec.

WC
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