Skip to main content
Topic: AC3 vs MP3 (Read 18982 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

AC3 vs MP3

Why hasn't anybody done a comparison of AC3 vs MP3.I remember i had a anime dvd and the opening was 192k AC3 so i demuxed it and it sounded so good.MP3 sounded nice but AC3 has good quality.I found that it is really hard to encode to AC3 though i just found a file could AC3 encode a think i can encode to AC3 in graphedit because it was a inf and a .ax.

AC3 vs MP3

Reply #1
I think that ac3 is based on mp2 and hence it's worse than mp3

edit: typos

AC3 vs MP3

Reply #2
Quote
I think that ac3 is based on mp2 and hence it's worse than mp3
[a href="index.php?act=findpost&pid=267320"][{POST_SNAPBACK}][/a]


No, AC3 isn't related to MP2. But both have similar efficiency, so indeed, there's no point comparing AC3 to MP3.

AC3 vs MP3

Reply #3
Quote
1. By 1989, advances in audio coding technology and DSP hardware made it possible to move from the AC-1 audio coding technology to the transform based AC-2 coding technology, simultaneously raising audio quality while reducing bit-rate

2. By Dec. of 1991, the first
AC-3 coded digital film, Star Trek VI, played in three theatres.


Quote
Fraunhofer received a patent in April 1989 for MP3 in Germany and in 1992 Fraunhofer’s algorithm was integrated in MPEG-1 for which the specification was published in 1993.


ummh, i think AC-3 is a transform based coding coz AC-2 is already transform baased coding
so conclution is AC-3 is not similar to mp2

Both mp3 and ac3 release around 1990, so i think they should be quite similar in quality (TECHNICALLY looking at the "year" factor)

Since mp3 (LAME) is well tuned and tested, while AC-3 is not, i would say mp3 is better

AC3 vs MP3

Reply #4
AC3 is surperior to mp3/2.
AC3 Is Good if you have a Hi Fi system for good sound.

AC3 Samples


AC-3 192 kbps RightMark Audio Analyzer test

Interesting

How to Convert WAV to AC3 using AC3Enc
-------------------------------------------------

    Run AC3Enc and then:


1. Tick the 2-ch Interleaved Input box.

2. Load in your WAV file (16bit Stereo 48khz).

3. Change the Output file name if you wish.

4. Leave the bit rate of the AC3 file to 192, Do NOT change anything else in there.

5. Hit the Start Encoding button. It can take 5-10min to do the conversion.

AC3 vs MP3

Reply #5
Quote
AC3 is surperior to mp3/2.
[a href="index.php?act=findpost&pid=267324"][{POST_SNAPBACK}][/a]


 

Nope, it isn't superior to MP3, and is most likely equivalent to MP2.

And what AC3 encoder are you using, precisely?

AC3 vs MP3

Reply #6
Quote
Since mp3 (LAME) is well tuned and tested, while AC-3 is not, i would say mp3 is better
[a href="index.php?act=findpost&pid=267323"][{POST_SNAPBACK}][/a]


yes but I remember when mp3 was just starting to get noticed it was on the news and it was saying mp3 was basically crap in hi fi systems when turned up loud.But AC3 was partly made for hi fi systems and to have Exellent sound.

AC3 vs MP3

Reply #7
Quote
Quote
AC3 is surperior to mp3/2.
[a href="index.php?act=findpost&pid=267324"][{POST_SNAPBACK}][/a]


 

Nope, it isn't superior to MP3, and is most likely equivalent to MP2.

And what AC3 encoder are you using, precisely?
[a href="index.php?act=findpost&pid=267327"][{POST_SNAPBACK}][/a]


Well 192 kbs AC3 sounds way better in stereo system than 192 kbs mp3 with lame and ff.

AC3 vs MP3

Reply #8
Quote
But AC3 was partly made for hi fi systems and to have Exellent sound.
[a href="index.php?act=findpost&pid=267328"][{POST_SNAPBACK}][/a]


AC3 was made mode than a decade ago by a company that didn't have a vast experience on audio encoding. Their expertise lied in analog noise reducing.

Where it lacks in efficiency, it compensates with high bitrates. That's why you will hardly see stereo AC3 streams at less than 192kbps. Quality degrades too quickly below that (interestingly, that's the optimal point for MP2 too)

AC3 vs MP3

Reply #9
no comment

Info

 

AC3 vs MP3

Reply #10
ac3 _sounds_ pretty good, but it borks badly on both transients and high frequency stereo image.

you can hear this plainly on a 192kbps encode.

anime might be slightly different because it's not a film track (though very similar).  it's basically centered vocals and foley, plus some music of varied complexity.  every anime soundtrack i've heard has been extremely clean.

contrast that with something like brazil which is also encoded in 192kbps.  it's come off the analog track for the movie, and has a wide stereo image plus an orchestral score that makes wide use of brass.  believe me, it sounds bloody terrible at 192kbps where an mp3 from the same source would be more or less transparent.

unfortunately, it's hard to make a comparison, because no doubt your mp3 file is transcoded off the 192kbps ac3 

if you can get a hold of an uncompressed stereo soundtrack for a movie, please provide us some samples so we can pit these codecs against each other.

another problem is what encoder is used.  roberto already asked but it bears repeating, as the quality of ac3 encoders varies greatly.

popular (expensive) encoders are Surcode and sonic foundry Soft Encode.  [edit] competent authoring houses will use special hardware encoders.

free encoders are ac3enc and liba52 based offerings (QuEnc will output ac3 if you feed it an avisynth script with an audio source, and turn video encoding off).

as far as i'm aware ac3 has only 1 block size, but i could be wrong on that.  anyway, for a good stereo encode, ac3 needs at least 224kbps - one would expect mp3 to be entirely transparent at this bitrate of course (and even so, ac3 will die as soon as it hits a transient).

AC3 vs MP3

Reply #11
The beauty of AC-3 is that is part of one of the most  solid standards in the world, DVD.
The ugly of it is that is a Monopoly-License Deal Dolby got and if you are not making 5.1 audio you are better off using MPEg layer II which is also part of the DVD standard.
This open the door to use every DVD box out there as an advanced audio jukebox.
In that sense MP2 and AC-3 are more popular than MP3.

Layer II at 192Kbps sounds good to me using Qdesign encoder.

Other than DVD use of AC-3 or Mpeg Layer II is pretty much obsolete. This  "OLD" codecs has been render a bit obsolete when compared to OGG Vorbis, AAC+ and MP3.

Adios,
Lucem

AC3 vs MP3

Reply #12
AC-3 is ugly because it was designed to contain movie soundtracks, not music. This creates all kinds of limitations. One of the biggest limitations is that the dynamic range between center channel (dialog) and the other channels is limited. And AC-3 allways applies dynamic compression so it isn't really suitable for music (ever wondered why most music dvds include dts sound?).

AC3 vs MP3

Reply #13
Quote
And AC-3 allways applies dynamic compression


not so.  it's stream allows for a dialog normalisation level (almost, but not quite, the exact same thing as ReplayGain) so compression can be applied  decoder-side, but of course any half decent decoder worth paying actual money for will allow you to turn this off.  my cheap-as-f Hyundai DVD player actually doesn't support DRC at all, and plays everything as it is stored in the file.  this is actually annoying if you like to watch movies and fry steaks at the same time, because all those dynamics mean you miss half the movie (and the loud bits shock you and make you drop the frypan).

true, i've seen DVD players that compress and don't allow it to be turned off (or simply conceal the option so well that i can't find out how to turn it off), but in my opinion these devices simply aren't worth buying.

DTS is usually more dynamic simply because it's received a different mastering.  otherwise people will never use it .  DTS is a far-inferior format to even ac3.  the only advantages it has is that it has 3 different block-lengths, so you'll never hear pre-echo with a competent encode, and it has a lossless mode (never used, and no standard allows for it).  it is subband based, making it in the same league as mp2, but it's psychoacoustics are woefully simplistic and it mutilates frequencies over about 12k.  IMHO DTS is just a huge waste of bitrate that could be used for better looking video or possibly one of those director's commentaries.

[edit]  it should be noted that i haven't ABX'ed DTS with anything.  i've made a couple of DTS CDs, but they are all but guaranteed to be transparent as they use such a massive bitrate (twice that of what goes on a DVD, and at 44.1k instead of 48k - no contest really)

AC3 vs MP3

Reply #14
Quote
no comment

Info
[a href="index.php?act=findpost&pid=267331"][{POST_SNAPBACK}][/a]


So what ?
Did you read it actually ?

Compared to MP3 the blockswitch mechanism of AC3 is useless (likely to lead to more pre-echo) and AC3 does not employ any sort of redundancy removal (like MP2) in a VLC sense (variable length codes, like huffman or arithmetic coding).


SebastianG

AC3 vs MP3

Reply #15
Quote
DTS is usually more dynamic simply because it's received a different mastering.  otherwise people will never use it .  DTS is a far-inferior format to even ac3.  the only advantages it has is that it has 3 different block-lengths, so you'll never hear pre-echo with a competent encode, and it has a lossless mode (never used, and no standard allows for it).  it is subband based, making it in the same league as mp2, but it's psychoacoustics are woefully simplistic and it mutilates frequencies over about 12k.  IMHO DTS is just a huge waste of bitrate that could be used for better looking video or possibly one of those director's commentaries.
[a href="index.php?act=findpost&pid=267415"][{POST_SNAPBACK}][/a]

For me even for movie ac3 isn't great. Each time I have a movie with ac3 and dts, ac3 and dts is easily abxable (a friend changed the audio track during the playback). It's a no brain and dts was way better. Better separation, better high frequencies. Now ac3 was 448kbs and dts was 768 kbs, but quality speaking dts is superior for me. Maybe the mastering is different but I have made this experience several times and each time dts was better. Probably dts is not a great codec in terms of compression but the quality is better at the bitrate commonly used.

edit: oops, I'm off topic

AC3 vs MP3

Reply #16
Now, now, now !

Has everybody forgotten the Terms of Service ?
This board is dedicated to scientific evaluation of codec quality, using exclusively double blind listening tests.

Geopoul, sound quality can't be evaluated from the origin of a codec.
Kotrtim, , sound quality can't be evaluated from the year of release of a codec.
MP34ever, sound quality can't be evaluated from RMAA analysis, even less from unfounded statements.
Rjamorim, sound quality can't be evaluated from unfounded statements.
Mp34ever, sound quality can't be evaluated from old rumours.
MugFunky, no we can't believe you because you don't provide ABX results for AC3, and make only hypothesis about what MP3 "should sound" !
SebastianG, sound quality can't be evaluated from the blockswitch mechanism of a codec.
Marcan, sound quality can't be evaluated from two tracks that are likely to come from different sources.

I'm sorry, but this kind of arguing about sound quality can't be allowed in Hydrogenaudio (see term of service number 8). This community was made especially to avoid this.

 
SimplePortal 1.0.0 RC1 © 2008-2019