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FLAC to AAC vs. WAV to AAC - Page 2

post #16 of 38
Generally AAC at 256 VBR is better than MP3 320. There isn't a whole lot of reason to use AAC 320 because the VBR lets it bump up to 320 if it needs it and lowers it if it doesn't. Always use VBR. It makes things sound better and makes the file size smaller too.
post #17 of 38
Quote:
Originally Posted by Posam View Post

Should I rip my CDs into AAC or an MPEG (both 320kbps). 

 

I'm going to assume you mean MP3.

 

Generally speaking, if you encode a 320 KBps CBR AAC and MP3, the AAC file would be smaller. Sound would be relatively identical, however. In theory, AAC is supposed to be a bit better in terms of audio quality, but that can be disputed as to whether or not it's even on an experienceable level.

 

As for which you should use, that depends. AACs are supported on most platforms but not all. If the gear you're going to use has support for AAC then go for it. Otherwise, MP3 is pretty universal.

post #18 of 38
Quote:
Originally Posted by bigshot View Post

Generally AAC at 256 VBR is better than MP3 320. There isn't a whole lot of reason to use AAC 320 because the VBR lets it bump up to 320 if it needs it and lowers it if it doesn't. Always use VBR. It makes things sound better and makes the file size smaller too.

How does it make music sound better by using a VBR? My CD rips are already in mp3 320kbps. 

post #19 of 38
Quote:
Originally Posted by mikeaj View Post

Depends what you mean, but the answer you're looking for is probably a "no."  There are mathematical limits to how much data can be compressed.

Different audio file compression algorithms / settings / formats will compress different files by slightly different amounts.  Maybe you could save a couple percent on a song's file size with APE as opposed to FLAC, or something like that.  Of course, all of these are compressed considerably compared to the original lossless WAV, but I don't think you're talking about that.

But if you're talking about "lossless audio quality" in the sense that you want something with audio quality as good as lossless to you, then you could do a lossy (psychoacoustic) compression to MP3 / AAC / Vorbis / whatever.  As people have been discussing, high-bitrate lossy encoding can reduce file size by a lot compared to lossless, yet it may sound identical (to you, under certain circumstances).

What I meant was if there was a way to reduce a FLAC file without losing the quality at all.
post #20 of 38
FLAC is already compressed as much as it's going to compress.
post #21 of 38
Quote:
Originally Posted by Posam View Post

How does it make music sound better by using a VBR? My CD rips are already in mp3 320kbps. 

I did comparison tests and I found that MP3 320 was almost as good as the original CD, but there was still a small amount of artifacting. I couldn't detect any artifacting at all with 256 AAC VBR. 320 LAME MP3 is as good as AAC 256 VBR though. With MP3s all encoders are not created equal.
post #22 of 38
Quote:
Originally Posted by Posam View Post

How does it make music sound better by using a VBR? My CD rips are already in mp3 320kbps. 

 

VBR means Variable Bitrate. It has no effect on sound quality at all. It's about only using as many bits of data necessary to present the music in the relative span it's been given. It works under the principle of why use all 320 Kbps when 294 Kbps will sound the same? If you're not doing VBR you're doing CBR (constant). a VBR encoded file will sound the same as a CBR encoded file but at a lower file size.

 

Quote:
Originally Posted by kineticwave View Post

What I meant was if there was a way to reduce a FLAC file without losing the quality at all.

 

Not really. It helps to think of FLAC as a playable ZIP for WAV files. That's over-simplifying things and works less and less the more you look at it, but for the sake of your question it's fine.

post #23 of 38
If you do 256 VBR the bitrate will go up as high as 320 if neessary. In this case, VBR does improve sound quality.
post #24 of 38
Quote:
Originally Posted by bigshot View Post

If you do 256 VBR the bitrate will go up as high as 320 if neessary. In this case, VBR does improve sound quality.

 

But not over a 320 file, be it VBR or CBR. It also depends on what you mean by VBR as not all VBR encoders are true VBR. Some constrain to +/- 20 where others allow for a more free range approach. With a true VBR the flexibility tends to go down rather than up.

post #25 of 38
There's no reason not to use VBR. If you're encoding below 320 it can raise the rate if needed, and if you encode at 320, it can save file size with no impact on quality.
post #26 of 38
Quote:
Originally Posted by DougofTheAbaci View Post

 

I'm going to assume you mean MP3.

 

Generally speaking, if you encode a 320 KBps CBR AAC and MP3, the AAC file would be smaller. Sound would be relatively identical, however. In theory, AAC is supposed to be a bit better in terms of audio quality, but that can be disputed as to whether or not it's even on an experienceable level.

 

As for which you should use, that depends. AACs are supported on most platforms but not all. If the gear you're going to use has support for AAC then go for it. Otherwise, MP3 is pretty universal.

This doesn't make any sense. How can one file at a constant 320 Kilobytes per second be smaller than another at 320 Kilobytes per second? They would be the exact same size, only the sound quality would differ. Also, it's worth mentioning Ogg Vorbis if you'll be playing music on devices that support it (such as Android).

Quote:
Originally Posted by Posam View Post

How does it make music sound better by using a VBR? My CD rips are already in mp3 320kbps. 

It wouldn't if you used the same encoder you did for your CBR 320 MP3.

Quote:
Originally Posted by bigshot View Post

If you do 256 VBR the bitrate will go up as high as 320 if neessary. In this case, VBR does improve sound quality.

Assuming you're comparing to a 256 CBR that would be correct, but a 320 CBR using the same compression method (AAC) would be equal in quality if not better (although certainly larger in size).

 

Edit: Also, as someone else said, it depends on the specific settings of the VBR encode. I know that the LAME MP3 encoder has both Average bit-rate and variable bit-rate settings, with the average setting guaranteeing a certain size while still allowing the bit-rate to change and the variable setting allowing for the bit-rate to adjust more freely to the music. Furthermore, there is then the option to choose how fast the bit-rate adjusts for the changing complexity of the piece. It's not a constant VBR that uses the exact same settings across all encoders.


Edited by Terminator02 - 8/26/12 at 8:20pm
post #27 of 38
AAC is smaller for the same sound quality. A 192 AAC file sounds about as good as a 320 MP3.

320 AAC CBR is overkill. It becomes completely transparent somewhere between 192 and 256. 256 VBR allows it to go lower if it doesn't need the bandwidth, and higher if it needs to go up. But in practice, I've seen 256 VBR come out around 210 or 220 tops.
Edited by bigshot - 8/26/12 at 11:46pm
post #28 of 38

Lossless formats use data-compression and can be 'de-compressed' to the original quality .

Lossy formats use data-reduction and can NOT be 'de-compressed' to the original quality, because the data just ain't there any more .

 

You do not need to extract a FLAC to WAV to transcode, it's slower to do so and makes absolutely no difference whatsoever on the final result .

 

And yes, you can hear the difference with A LOT of source-material, like classical music.

Why not convert to ALAC, that should work on all apple-gadgets ?


Edited by AKG240mkII - 8/27/12 at 2:20am
post #29 of 38
Quote:
Originally Posted by AKG240mkII View Post

Lossless formats use data-compression and can be 'de-compressed' to the original quality .

Lossy formats use data-reduction and can NOT be 'de-compressed' to the original quality, because the data just ain't there any more .

 

You do not need to extract a FLAC to WAV to transcode, it's slower to do so and makes absolutely no difference whatsoever on the final result .

 

And yes, you can hear the difference with A LOT of source-material, like classical music.

Why not convert to ALAC, that should work on all apple-gadgets ?

 

Lossy formats like AAC use both compression and reduction, as far as I'm aware. It's one of the ways it can be smaller than MP3.

 

I agree, about FLAC v. ALAC, though. If you use Apple products there's no reason not to go ALAC. You can even make the argument that it's better to go ALAC with Android because most Android phones, I believe, should have hardware support for MPEG formats like H.264 and M4A (which includes ALAC). It doesn't mean better sound quality but it does mean better battery life.

 

Quote:
Originally Posted by Terminator02 View Post

This doesn't make any sense. How can one file at a constant 320 Kilobytes per second be smaller than another at 320 Kilobytes per second? They would be the exact same size, only the sound quality would differ. Also, it's worth mentioning Ogg Vorbis if you'll be playing music on devices that support it (such as Android).

 

It's not worth mentioning Ogg because it's got the most limited support of any of the major audio formats, doesn't have the best quality/size ratio and wherever it is supported better formats are also found. In other words: Don't bother with it.

 

As for how, it's the same way you can compress a folder into a ZIP and RAR archive and get two different file sizes that contain the same data: Compression algorithms. MP3 is an older file than M4A (AAC).

post #30 of 38
Quote:

Like MP3, AAC encoding reduces the complexity of the audio signal by progressively simplifying or removing peripheral elements of the signal.

The audio is split into various frequency bands and psycho-acoustic modelling is used to determine which bands can be least noticeably reduced in complexity,

thus reducing the amount of data needed to express them in digital form, and thereby the total size of the file.

 

http://www.jiscdigitalmedia.ac.uk/audio/advice/aac-audio-and-the-mp4-media-format/#aac-basics

 

Lossless formats use non-destructive compression, lossy formats use destructive 'compression' ..

Except it isn't compression, it's data-reduction ..

 

Lets say you want to compress a can of air .. Do you remove some of the air and call it compressed ?

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