128 AAC vs 128 MP3
- Thread starter bjurusik
- Start date
Koelling
I Think Different
128 is 128 kbs. The song files are the same size (or should be). The quality is the difference. Apple actually went back to the original artists for music so the loss experienced in making a CD isn't noticable. I can't tell the difference but that's what it is, quality at the same bitrate.
monktus
Registered
128 mp3 isn't great (in fact sometimes it can be pretty awful) compared to 160. I ripped Point by Cornelius at 128 AAC and the file sizes were quite good (less than a meg a minute) and it sounds lovely. I'm very happy that they finally added aac support to the ipod. All Apple need to do now (apart from set up billing for music store outside the US!!!) is give old ipod users in the fly playlists. Oh and maybe tetris!
mr. k
Registered
on macrumors.com a week back there was an article comparing aac and mp3 - it said that listeners with tuned ears could not tell the difference between an mp3 above 256kbps ( anything lower and they knew it wasnt a cd ) but for aac the different point was 128kbps... seems great, i can cut my library almost in half 
and does anyone know if its possible to turn mp3 into aac? would be easier to reburn everything.
and does anyone know if its possible to turn mp3 into aac? would be easier to reburn everything.
Gnomo
Registered
I'm sure you can, but the real question is: Would you really want to?
If you already lost data due to compressing a wav into an mp3, would you really want to possibly lose even more converting it into a aac? or even if you don't lose any data, you will still have a aac that doesn't sound as great as it could. Personally all the songs that I can I'm re-ripping.
binaryDigit
Registered
No, 128kbs is the bit _rate_ and _not_ a measure of size. The compression ratio is related, but not the same thing. If you have a higher bit rate, you are storing more data per given time frame, which means that you have to compress more data for given time frame. So a higher bitrate sample will take up more space than a lower one FOR ANY GIVEN COMPRESSION CODEC. However, different codecs compress with different efficiencies AND quality. Both mp3 and aac are lossy algorithms, you actually lose data compared to the original. The "magic" is in the codecs ability to decide what to remove and to do it in such a way as to make it inaudible as possible.
Sure, if you want worse quality than the original mp3. As stated above, MP3 is a lossy compression, you lose information in the compression process. This information is lost, as in can't be restored. The algorithm relies on the fact that you won't "miss" the data that it chucked. What that means in your case is that you want to compress something where information has been lost with another program that will toss even more information. At best you'll have something no better than the mp3, most likely you'll get something a bit worse. So if the point of moving to aac is to have smaller files with better fidelity, you have to go back to your originals.
That's entirely up to you. Play with different settings and see what you like. Could be that 128 is fine, could be that you actually notice a difference and want to go higher. This is highly subjective. One other thing to keep in mind is that different music is affected differently by the algorithms, so death metal might sound fine, while baroque might sound better at a higher rate (or vice versa). Also depends on what and where you listen. If it's with an ipod with bud plugs, then a loss of bass due to lower bitrates might not matter. Then again a loss of high end due to lower bitrates might be more noticable if you have a pair of Stax hooked up to your iPod vs listening to it over you car stereo. So use 128 as a starting point and play play play until you find what is right for you.
I think i might have found a drawback from AAC vs mp3.
I've ripped some cds to 128k AAC and I find that intermittent in songs it tends to kinda "get quiet" thats the best way I can describe it. Can anyone else hear it? Its noticeable when I have the speakers up loud. You can hear it kinda fade to the back. I'm not sure how to explain it.
I've ripped some cds to 128k AAC and I find that intermittent in songs it tends to kinda "get quiet" thats the best way I can describe it. Can anyone else hear it? Its noticeable when I have the speakers up loud. You can hear it kinda fade to the back. I'm not sure how to explain it.
dave17lax
Inventor of the Egg Wave
I know you said it's hard to explain, but could you try? Like is it being encoded at a lower volume or is it just suddenly getting the wind knocked out of it? I unfortunately don't have time to play with this stuff like I used to. My fault I guess for working at a bank instead of pursuing my major (art)
Well I can best describe it as the song losing its volume. Its very subtle. I'm still trying to figure it out. I don't know if its the AAC format (i found it on 160kpbs and 128 kbps rips in the format) or if its something else like my computer. I've used headphones and my studio speakers and does the same.
It is not like its losing its total volume in the encoding. It still sounds the same but like in some moments in the song it will do a "dip" in volume. It is real quick. I'm thinking half a second or so and it comes back.
I guess I have a discerning ear. I could always here the hiss and fuzz even on subtle mp3s. But if you crank a good rock song you can hear this AAC stuff. Its like it loses its thunder for a half second or so. I'm not sure still if its AAC i'm still trying to figure it out.
It is not like its losing its total volume in the encoding. It still sounds the same but like in some moments in the song it will do a "dip" in volume. It is real quick. I'm thinking half a second or so and it comes back.
I guess I have a discerning ear. I could always here the hiss and fuzz even on subtle mp3s. But if you crank a good rock song you can hear this AAC stuff. Its like it loses its thunder for a half second or so. I'm not sure still if its AAC i'm still trying to figure it out.
I think I'm hearing the same thing you are. On my Sennheiser 600's I hear what you are explaining. Sort of like a fading or pulsing of volume in certain parts of the song. The AAC format definately sounds better than MP3 however, so I don't really mind. So far I've downloaded about 50 songs from the Apple music service and they are all really great quality. I am very pleased. I wasn't a big stealer of music, mostly because the quality was almost always fairly bad. Now I can download the music I want at CD quality or better. Awesome.
bah!
mp3's suck and i'm sure AAC sucks ass too.
Shorten
http://research.umbc.edu/~hamilton/shnlinks.html
FLAC
http://flac.sourceforge.net/
mp3's suck and i'm sure AAC sucks ass too.
Shorten
http://research.umbc.edu/~hamilton/shnlinks.html
FLAC
http://flac.sourceforge.net/
I was talking earlier about how I found that in AAC the files lose volume at times. Well I think I might have narrowed it down.
I think while doing other cpu intensive tasks is when it happenend. I'm wondering if the cpu is taxed more when playing AAC's and somehow i was doing to much while playing them.
This is only a theory.
Oh and also. I downloaded my first song from apple music service and I can't hear this problem at all on the song.
I think while doing other cpu intensive tasks is when it happenend. I'm wondering if the cpu is taxed more when playing AAC's and somehow i was doing to much while playing them.
This is only a theory.
Oh and also. I downloaded my first song from apple music service and I can't hear this problem at all on the song.
Jason
Eyebrow Moderator
Summing up... The bitrate decides what size the file will be at the end, because 128 kbps means kilo-bits-per-second, so a 3 minute song will always be 2880 Kb. Advanced encoders actually do VBR (variable bit rate), so your mileage may vary depending on the song's 'encodability' (can the decoder switch to a lower bitrate at some parts...).
Whatever Apple or the MPEG group says: AAC is - like MPEG 1 Layer 3 (MP3) - a 'lossy' codec. They say it's better than MP3, so you're able to get about the same quality at 128 kbps that you get with a 160 kbps MP3. So you save some space. That's why the new iPods are advertised as being capable of holding more tracks.
Whatever Apple or the MPEG group says: AAC is - like MPEG 1 Layer 3 (MP3) - a 'lossy' codec. They say it's better than MP3, so you're able to get about the same quality at 128 kbps that you get with a 160 kbps MP3. So you save some space. That's why the new iPods are advertised as being capable of holding more tracks.