Should I convert all my audio to 256 AAC?

Discussion in 'Digital Audio' started by DaGrandMastah, May 3, 2012.

  1. DaGrandMastah macrumors 6502a

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    Mar 19, 2011
    #1
    Hi all, I'm currently researching what the best route is to go with when converting over my CD library. I realize that everyone loves Lossless (which I'll use for archiving the CD's) but I'm looking for "the best" lossy encoding.

    I was originally planning to encode all my CD's into 320 CBR but it seems that almost everything I read states that this is a waste of space as their is nary a difference (except to the most trained ears) between 320 CBR and VBR v-0. Ultiamtely, I don't mind the difference in space when on my computer hard drive but it does become more of an issue when uploading to my iphone for portable listening so then I switched course and started thinking I would go with VBR v-0 (I posted a similar question to this in the mp3 forum) but now I'm reading that I may even be better off going with AAC 256?

    This may make the most sense for me being that I'm a Mac user (imac, iphone, ipad) and I'm going to playing all my music out of my itunes library.

    Is there any reason I would regret the decision to go AAC over mp3?

    Also, for those with experience with this, could you direct me to the best possible setting to use in XLD for encoding CD's/FLAC files to aac?
     
  2. dj-anon macrumors member

    dj-anon

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    Mar 23, 2011
    #2
    Well, if you really care about audio quality with lossy encoding, the only and best way to determine what format is the best is to perform an ABX test:

    http://www.hydrogenaudio.org/forums/index.php?showtopic=16295
    http://emptymusic.com/software/ABXer.html

    Now, from my experience, mp3@320kbps is around the same quality as aac@128kbps. Even at 256kbps, the file size of an aac is about the third of an mp3 at maximum quality.

    About FLAC, I'd just use ALAC instead, if it is only for archival purposes. Very straightforward to rip (no settings) from iTunes or from XACT (http://www.macupdate.com/app/mac/14246/xact).
     
  3. DaGrandMastah thread starter macrumors 6502a

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    #3
    My main concern here is making sure I'm as future proof as I can be. A looooong time ago, I thought I was ok with just using real media music files (converted from crappy 128 kb mp3's LOL) and that obviously changed. I'm not sure I'll ever really tell the difference between 192 and 256 and 320....but I do know that I don't want to have to reencode everything again.

    I realize CBR is basically a waste of space so now I'm just trying to decide if I'm better off with AAC or VBR v-0.

    What settings would you recommend for AAC using XLD? True VBR?
     
  4. mike457, May 3, 2012
    Last edited: May 3, 2012

    mike457 macrumors 6502

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    Ontario
    #4
    I have two separate iTunes libraries. The one that I use for listening at home is set up as Apple Lossless. Like you, I rip my CDs and store them in that format. The second library is set up for 256AAC, and I use that for syncing with my iPad and iPhone. I listen mostly to classical, some of which can be quite demanding. I tried different encoding rates, and I found that in most cases, I could not really hear the benefit of going 320 (except with decay sounds on some harpsichord/piano/harp recordings). I can clearly hear a difference on pretty much anything below 256, though. As long as you're using Apple devices, 256AAC should be good. It also streams well through a DNLA server to my receiver, which ALAC won't do.

    I use True VBR, encoding quality Max. With a lot of the files, I have used Join Together, to put the movements of a symphony into one piece (for example), and I think that's CBR.
     
  5. dj-anon, May 3, 2012
    Last edited: May 3, 2012

    dj-anon macrumors member

    dj-anon

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    Mar 23, 2011
    #5
    That's what the lossless backups are for. If you need to reencode, you don't have to rip everything again, you just have to convert the lossless files to the new desired format.

    That being said, AAC audio is a standard for the audio and video industry, and for the web too. AAC is not going anywhere.

    I'd say you should discard mp3 as an option, they are too big in file size and not as efficient as aac. If you encode your songs at 256kbps (VBR, constrained, maximum encoding quality) you'll have virtually equivalent files, in size and quality, to those in the iTunes store.

    Edit: You can also use True VBR 110.
     
  6. paolo- macrumors 6502a

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    #6
    Isn't there an option to encode as you upload?
     
  7. mannix87 macrumors 6502

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    in the southeast
    #7
    ^ yes. Just go to itunes preferences & you.ll see it there
     
  8. DaGrandMastah, May 3, 2012
    Last edited: May 3, 2012

    DaGrandMastah thread starter macrumors 6502a

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    #8
    What's the difference between True VBR 110 and VBR Constrained? Now I'm jus trying to figure out a happy medium on what encoding settings to use in xld.

    I just tested it out and True VBR 110 is giving me a slightly larger file size then vbr v-0. I thought AAC was supposed to be smaller though?


    EDIT - I tested it out on some other tracks and they come out lower so I'm gonna assume that it's where the true VBR comes in. The mp3 is a constrained vbr at a certain nitrate but true vbr actually allows it to exceed those constrained settings when needed?
     
  9. DaGrandMastah thread starter macrumors 6502a

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    #9
    Where do you leave the target quality? That's the setting that's confounding me the most.
     
  10. dj-anon macrumors member

    dj-anon

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    Mar 23, 2011
    #10
    True VBR 110 will give you a (bit) smaller file than with the constrained setting. No human ear should be able to tell the difference in sound quality between the two.

    MP3 with -v 0 varies its bitrate between 220-260. Like I said, an mp3@320kbps cbr, is somewhat equal to an aac@128kbps.

    If you really want a smaller file size, you could use VBR constrained @ 192 or even 160kbps. That would result in an even smaller file and still superior to mp3@320kbps, and obviously -v 0.
     
  11. mike457 macrumors 6502

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    Ontario
    #11
    I have to admit I've always left that at the default. I don't know what it's supposed to do, so leaving it alone has always seemed the most painless route.
     
  12. DaGrandMastah thread starter macrumors 6502a

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    Mar 19, 2011
    #12
    Which setting would recommend?

    VBR constant at 256 with max quality

    True VBR 110

    True VBR 127 (not sure if this is just a waste of space).
     
  13. dknightd macrumors 6502

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    Mar 7, 2004
    #13
    I'd rip alac, then let itunes downsample to acc of your chosen bitrate when loading your ios device.

    No need to maintain separate libraries anymore IMO.
     
  14. Scarpad macrumors 68000

    Scarpad

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    #14
    Well you might be missing Artwork Itunes strips it to my Ipad and Iphone on conversio of the lossles files to lossy
     
  15. prestomusic macrumors regular

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    Oct 26, 2010
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    Brisbane, Australia
    #15
    You say HD space on your computer isn't such an issue so just encode AAC at whatever rate makes you 'happy'. Mobile storage space will only continue to increase. If you're this concerned about the choice then I reckon your better of tending towards a higher bit rate. Nothing worse listening and thinking you went too low, and looking back in a year or too and thinking you need to redo it all.
     
  16. dknightd, May 15, 2012
    Last edited: May 15, 2012

    dknightd macrumors 6502

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    #16
    I don't have that problem

    edit - Ooooops - I just noticed all my artwork is gone! I'm sure this used to work. I wonder what changed? Could be different itunes software, or, different iphone software - or both. Kind of annoying . . .
     
  17. Scarpad macrumors 68000

    Scarpad

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    Ma
    #17
    It's a bug have'nt checked 10.6.3 yet
     
  18. ChrisA macrumors G4

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    Jan 5, 2006
    Location:
    Redondo Beach, California
    #18
    The trouble with that test is that conversion quality is not constant over time. For example 256K MP3 might be good enough. You might listen to 10 songs and then there just one drum solo on the 11th song that has an encoding artifact. What I found is that only some passages on some songs were "bad" using MP3.

    So that ABX test works but just be sure to listen for a few days to each sample. a few seconds is NOT long enough.

    The things that are very hard to encode as "electronica" and some drums. These signals are more compllae than a typical acoustic instrument

    ----------

    Then your ONLY choose is lossless. If you use any kind of lossy format you are only "future resistant." What happens is that one day you might buy some better, more high-end step gear. Oe even worse, do what I did and take piano and guitar lessons and then your ear starts to pick up stuff you used to miss. Actually I did both and now I'm noticing more defects but now most of those are in the CD. Some vintage recordings that were done on tape on 50's vintage equipment.

    "future proof" means to not loose any bits. And what's the point? you can buy a 1TB disk drive for $100 now and with that you can store 2,000+ uncompressed CDs. at a cost of 5 cents for each CD. Is that really to expensive?
     

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