Anyone have any tips for mass AAC Converting/Re Ripping?

Discussion in 'Mac Help/Tips' started by bennetsaysargh, Apr 28, 2003.

  1. bennetsaysargh macrumors 68020

    bennetsaysargh

    Joined:
    Jan 20, 2003
    Location:
    New York
    #1
    does anyone have any tips for mass AAC Converting/Re Ripping? i go to middle school, and want to have all about 2000 of my mp3s into AAC by friday when i will be getting my iPod. all of my music not on CDs is my biggest concern. those I cant get rid of because those are cds that i have either broken, or let people borrow and they never returned it.:rolleyes: i could burn them onto cd-rs, but i only have about 5 left and my dad will get mad if there are no more cd-rs left.

    thanks for any help!


    Ryan
     
  2. GeeYouEye macrumors 68000

    GeeYouEye

    Joined:
    Dec 9, 2001
    Location:
    State of Denial
    #2
    Go buy more CD-R's. Personally, I'm going to re-rip from CD, but any *ahem* other MP3's stay as they are - transcoding isn't a good idea, as it'll most likely result in a loss of quality.
     
  3. Macpoops macrumors 6502

    Joined:
    Jan 15, 2002
    Location:
    PA
    #3
    The only way to fully take advantage of AAC is re-ripping them from the ORIGiNAL source. Burning them on the CD then re-ripping them is not the same thing, because you are making a copy of a copy. Let me explain. You buy the original CD(Master), Then you rip it to Mp3(Second Copy), in that process chunks of information are lost. Now lets say you make a CD from those Mp3s (Third Copy) you don't get the original quality back because you already lost the additional information all you get is the remaining information inflated to AiFF. So now you have a Mp3 quality Audio CD, not an original quality on. SO now your going to take your MP3 sound quality CD and rip it to AAC(4th Copy). From that your will get an even lower quality AAC then from ripping it straight from the original CD. Each time you make a copy of a copy regardless of the codec you are losing information.

    All i am saying it is a bad idea to convert your MP3s to AAC because they will be lower quality. If thats what you want then it's your decision. I just don't think it is very smart
     
  4. bennetsaysargh thread starter macrumors 68020

    bennetsaysargh

    Joined:
    Jan 20, 2003
    Location:
    New York
    #4
    almost all of my MP3s are either 256kbps or 320kbps. i don't there will be a loss in quality.
    if there is a batch AAC audio converter besides iTunes, i would be happy:)
     
  5. cb911 macrumors 601

    cb911

    Joined:
    Mar 12, 2002
    Location:
    BrisVegas, Australia
    #5
    hhmmm... there might be something on versiontracker.com, you should check that out.
     
  6. hugemullens macrumors 6502a

    hugemullens

    Joined:
    Dec 15, 2002
    Location:
    Michigan
    #6
    If all your mp3's are 256 kb/sec just leave them be. AAC will sound worse if you go from mp3 to AAC and its almost impossible to tell a 256 mp3 from an actual CD. and yes, there will be a loss of quality if you do it.
     
  7. ibookin' macrumors 65816

    ibookin'

    Joined:
    Jul 7, 2002
    Location:
    Los Angeles, CA
    #7
    There IS a batch converter in iTunes. All you have to do is select AAC encoding in the Preferences (Importing section) and an option to convert to AAC appears in the "Advanced" menu. Just select you're entire library and click that.

    Word of warning: Depending on the speed of your computer, it could take DAYS to do this. On my iBook 800, it would have taken a little less than a day of straight encoding to convert my 2500 MP3s. That's why my G4 iMac is doing it right now...
     
  8. bennetsaysargh thread starter macrumors 68020

    bennetsaysargh

    Joined:
    Jan 20, 2003
    Location:
    New York
    #8
    i know about the batch converter in iTunes, but i was kinda looking for another one to see if it's better. i'll look in versiontracker when i get home from school.

    have a good day everyone!
     
  9. peterjhill macrumors 65816

    peterjhill

    Joined:
    Apr 25, 2002
    Location:
    Seattle, WA
    #9
    you are better off re-ripping. That is what I am doing right now. I put a cd in, find it via browse in my library, delete the original mp3, rerip to aac, find the cover art with google, when it is done ripping, copy the art to the tracks, and repeat.
     
  10. stuartmingay macrumors member

    Joined:
    Apr 10, 2002
    #10
    190 kbps MP3 to 128 kbps AAC.

    Hi,

    Just like to add my question to the debate:

    99.9% of my 1800 MP3s are ripped direct from the CD at 190 kbps (the highest iTunes could offer I think). I haven't downloaded Quicktime 6.2 yet (that's for tonight), but if iTunes has this batch conversion utility then Apple don't seem too concerned about loss of quality.

    Q: Will batch converting using the above bit-rates result in:
    A - Smaller AAC files with the same quality as the MP3s,
    B - Smaller AAC files but worse quality,
    C - Similar size files, with the same quality, or
    D - similar size files but with better quality

    Cheers guys,

    Stu
     
  11. iGav macrumors G3

    Joined:
    Mar 9, 2002
    #11
    Re: 190 kbps MP3 to 128 kbps AAC.

    iTunes can encode way above 190 kbps... it goes up to 320 kbps!!

    Answers to your questions can be found here...

    http://www.apple.com/mpeg4/aac/

    and here...

    http://www.macrumors.com/pages/2003/04/20030418170551.shtml
     
  12. barkmonster macrumors 68020

    barkmonster

    Joined:
    Dec 3, 2001
    Location:
    Lancashire
    #12
    Q: Will batch converting using the above bit-rates result in:

    A - Smaller AAC files with the same quality as the MP3s

    YES, if it's ripped from either CD or uncompressed AIFF/WAV/SDII format

    NO if it's converting an MP3 to AAC, it's already compressed, you'd lose a lot of fidelity.


    B - Smaller AAC files but worse quality

    NO, an AAC file at 128Kbps is reported to be the equivelent to a 256Kbps mp3, it's certainly better than a 192Kbps mp3 to my ears.

    YES if it's MP3 -> AAC

    YES if you're encoding at anything less than 128Kbps (or 64Kbps in mono). AAC lowers the samplerate at lower bitrates, that means you're losing far more quality than Mp3 would because you can encode a mono mp3 at 48Kbps and it will still be 44.1Khz but AAC would drop that down to 32Khz, defeating the purpose of the higher quality codec.

    Generally speaking, with any audio codec, encoding mono audio at exactly half the bitrate of stereo audio offers equal quality.

    It's claimed that AAC is twice the quality of MP3 at equal bitrates, here's some examples for comparison :

    I ripped the audio directly from CD using an external CD writer and a sample editor, I then converted the file from stereo to mono and cropped it to a few bars, saving it as a 44.1Khz mono AIFF to encode from. AAC files encoded with Quicktime 6, MP3 encoded with iTunes.

    Uncompressed 44,1Khz mono AIFF file : The file all other files were encoded from (1.2Mb)

    64Kbps Mono AAC : Equivelent to 128Kbps stereo AAC (120K)

    64Kbps Mono MP3 : Equivelent to 128Kbps stereo MP3 (120K)

    48Kbps Mono AAC : Equivelent to 96Kbps stereo AAC (90K)

    The 48Kbps AAC file, even though it's been encoded from the 44.1Khz AIFF file, is only 32Khz. Here is an Uncompressed 32Khz mono AIFF (920K) version for comparison.

    The difference between 44.1Khz and 32Khz is VERY apparent whether it's AAC or Uncompressed AIFF.

    The difference between the 64Kbps MP3 and AAC files is also quite obvious.

    The AAC file is very close to the quality of the original 44.1Khz AIFF file.

    C - Similar size files, with the same quality

    A 256Kbps AAC file sounds identical to the original CD track. A 256Kbps Mp3 sounds close to an original CD track.


    D - similar size files but with better quality

    A 128Kbps AAC is far higher quality compared with a 128Kbps MP3.


    The music in the example files is a few bars from "finished symphony" by Hybrid. It features a lot of very distinctive, high octave synth sounds along with a 90 piece Orchestra and breakbeats. The tune has huge frequency range and taxes any codec.
     
  13. jMc macrumors 6502

    jMc

    Joined:
    Nov 19, 2001
    Location:
    London N8, Late-16th Century
    #13
    Re: 190 kbps MP3 to 128 kbps AAC.

    The 'batch conversion' in question is just the old 'Convert to Whatever' option in the advanced menu. If you have MP£ as your ripping pref it would still say 'Convert to MP3'. I have always used it to convert AIF sound files that I've downloaded.

    jx
     
  14. Le Big Mac macrumors 68020

    Le Big Mac

    Joined:
    Jan 7, 2003
    Location:
    Washington, DC
    #14
    Re-ripping

    If I've already ripped a cd into mp3, and I stick the CD in with preference set to rip using AAC encoding, will it just replace the song files, leaving all the other information intact (song names, album, ratings, etc.)?
     
  15. stuartmingay macrumors member

    Joined:
    Apr 10, 2002
    #15
    Ah, the custom option ...

    ... that I never bothered with! So that's where 320kbps comes from.

    I'll check out the links to the audio files, but I may have to do a quick experiment myself as well!

    Stu
     
  16. mnkeybsness macrumors 68030

    mnkeybsness

    Joined:
    Jun 25, 2001
    Location:
    Moneyapolis, Minnesota
  17. King Cobra macrumors 603

    Joined:
    Mar 2, 2002
    #17
    First, if you were to encode 2000 songs from a source (avg. 4 minutes) to AAC it would take about 13 hours at a 10x multiplier.

    Second, AAC is more than twice as effective as MPEG-1 audio. I used to encode my music into MPEG-2 before iTunes 4 came out.

    Comparison:
    Test length and bitrate in Kbps: 3:09; 64 + VBR for the MPEG-2 file, 64 for AAC

    Results:
    MPEG-2 file did not have as high frequencies and was 1.5MB.
    AAC file have the higher frequencies and was 1.4MB.

    Third:
    >If I've already ripped a cd into mp3, and I stick the CD in with preference set to rip using AAC encoding, will it just replace the song files, leaving all the other information intact (song names, album, ratings, etc.)? (Le Big Mac)

    It should not replace any files. Here's why.

    Let's say you import two CDs and you do not give an author, album, or title to any song. The first album imports the songs as follows:
    Track 01.m4a
    Track 02.m4a
    Track 03.m4a
    etc.

    Now you do the same for the second CD. The files, again, have no defined author or album. Therefore, they would be placed in the same folder as your previous songs. An extra number is placed beside each track so this difference can be distinguished.
    Track 01 1.m4a
    Track 02 1.m4a
    Track 03 1.m4a
    etc.

    You do the same for a third CD.
    Track 01 2.m4a
    Track 02 2.m4a
    Track 03 2.m4a
    etc.

    If the first CD is imported through .mp3 and the second through .aac these are two different extentions. So this should be your import:
    CD1:
    Track 01.mp3
    Track 02.mp3
    Track 03.mp3
    etc.

    CD2:
    Track 01.m4a
    Track 02.m4a
    Track 03.m4a


    mnkeybsness: saw your post below. I did have .aac. It is realy .m4a as he pointed out. No intentional confusion meant.
     
  18. mnkeybsness macrumors 68030

    mnkeybsness

    Joined:
    Jun 25, 2001
    Location:
    Moneyapolis, Minnesota
    #18
    ripping cds with itunes puts the song name.m4a, not aac

    EDIT:
    it's cool...i was just clearing up if anyone got confused.
     

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