[cowpat]

does anyone else think there's just something a bit wrong about the idea of VBR? Having an unthinking computer decide whether something "deserves" to have a higher bitrate, and so constantly flicking between many different levels of quality?

Does anyone take a stance against it, or has anyone noticed any sound quirks that would set it apart from a constant bitrate of a similiar quality? It seems to me that some realism could be sacrificed by the constant changes, and a lot of my music ends up at around 200kbps - does this mean that the difference between that v0 file and a 320kbp mp3 is negligible, or is the computer just taking a "that'll do" attitude.

all a bit jumbled i know, but i just got my laptop back from the shop with all my files lost (sadface) so i have to re-upload all my CDs again (super sadface). I just wanted to see what you audio bods thought on the topic, and if this is just a psychological barrier on my part

also, sorry if this is the wrong board

 

[Pangaea]

I would think a computer is completely capable of this task, as all it is doing is measuring how much data a passage requires. I mean you can get readouts on sound that tell you the same thing.

In simple terms It just takes more data to articulate Beethoveen than Joey Ramone. Personally, if you gotta start over, just rip lossless- if you stay here long enough you'll get to that point someday anyway.

 

[monolith]

VBR makes a heck of a lot more sense than CBR. The computer is already deciding what needs to be there and what doesn't when encoding the mp3. If it sees that certain parts of the file don't need a ton of bits to be represented accurately, I'll certainly take the smaller size.

V0 and 320 are indistinguishable.

 

[Orcin]

If you are ok with compressed files to begin with... i.e. letting the computer decide which parts of the data to omit, it doesn't seem like much of a leap to go with VBR. To answer your main question, it really depends upon your hearing and only you can decide if VBR is ok. For me, I can't tell the difference between 256VBR and lossless ON MY PORTABLE RIG.

 

[krmathis]

Quote:

Originally Posted by Orcin /img/forum/go_quote.gif If you are ok with compressed files to begin with... i.e. letting the computer decide which parts of the data to omit, it doesn't seem like much of a leap to go with VBR.

x2
When encoding with a lossy encoder there are imo far more important things to care about than letting the computer decide which bitrate is the "optimal" for a specific amount of data.
I would be more worried about which data it decide to throw away during the lossy stage.

For lossless it makes no sense to go CBR at all though.

 

[cowpat]

to be honest, i have absolutely no idea how any of this stuff works, i suppose the "letting your computer decide" argument doesn't really stand up when comparing to other lossy formats. I think it's probably just a psychological thing - seeing the bitrate counter on winamp fluctuating constantly is a bit disconcerting really - Basically, i think i just needed some people who know more than me to give me some reassurances

As for lossless - i don't think it's worth it for me right now. I only listen to mp3s on the move (so battery life is a concern as well) and my equipment is still pretty basic in the grand scheme of things.

 

[r@mside]

Rip to lossless anyway.

Encode to VBR mp3s as you sync to your player. You then retain option of changing to 320 CBR or lossless for your DAP should you decide it's necessary in future.

 

[PixelSquish]

vbr seems to me to be inherently better since many parts of any song can be so different in density of sound it makes sense that one size does not fit all.

 

[majkel]

Talking about true VBR and mp3 is a mistake. The VBR mode in mp3 has got nothing common with truly VBR algorythms implemented in mpc, ogg or aac. The mp3 format uses only predefined bitrates per frame which are: 32, 48, 64, 96, 128, 160, 192, 224, 256, 320kb/s and the encoder chooses one specific bitrate per frame which finds "sufficient" for a given quality level. In LAME you set it with the -Vx suffix for the VBR mode. However, saying V0 is indistinguishable from the 320kb/s is both perceptionally (I hear it) and theoretically wrong. People forget that there is another original alghorytm called "bit reservoir" invented in original FhG codec which lets "moving" some bit reserve from one frame to another, keeping the average bitrate per the CBR setting (say 320kb/s here) but letting cover higher need for the bits in one frame when there is not so much needed in the other, from the direct neighborhood.
AAC, ogg Vorbis or mpc have no defined frame sizes, they can shrink or extend very high just keeping the average bitrate in the ABR mode, or fulfilling the applied quality level (VBR mode).

 

[Febs]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif However, saying V0 is indistinguishable from the 320kb/s is both perceptionally (I hear it) and theoretically wrong.

I know that you've claimed to be able to distinguish a LAME-encoded 320kbps MP3 from the original, but can you distinguish a V0 MP3 from the 320kbps MP3?

 

[LnxPrgr3]

Both CBR and VBR actually allow variation in size between frames, based on the number of bits the encoder thinks the sample needs. There are a couple differences though -- with CBR, you can only borrow bits from the limited bit reservoir saved up from using fewer bits in previous frames.

Also, at least in LAME, bit allocation for a frame in CBR is decided by an estimate of what they call "perceptual entropy" -- a guess as to how hard the frame is going to be to encode. The VBR algorithm (actually, algorithms, for LAME -- there's two VBR modes) uses a more advanced strategy.

 

[majkel]

Quote:

Originally Posted by Febs /img/forum/go_quote.gif I know that you've claimed to be able to distinguish a LAME-encoded 320kbps MP3 from the original, but can you distinguish a V0 MP3 from the 320kbps MP3?

Sure, I do. It's even easier due to cold/incomplete midrange timbre in the -Vx encoding modes. The LAME 320kb/s mp3 is even slightly overcolored but I don't mind it, it's pleasant to listen to sometimes.

 

[ILikeMusic]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif Sure, I do. It's even easier due to cold/incomplete midrange timbre in the -Vx encoding modes. The LAME 320kb/s mp3 is even slightly overcolored but I don't mind it, it's pleasant to listen to sometimes.

Oh please...

 

[monolith]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif Sure, I do. It's even easier due to cold/incomplete midrange timbre in the -Vx encoding modes. The LAME 320kb/s mp3 is even slightly overcolored but I don't mind it, it's pleasant to listen to sometimes.

You should go have some scientific tests conducted. If you can truly hear everything you say, I imagine you'll be quite a curiosity to scientists. They aren't used to superhumans.

 

[Packgrog]

Quote:

Originally Posted by Febs /img/forum/go_quote.gif I know that you've claimed to be able to distinguish a LAME-encoded 320kbps MP3 from the original, but can you distinguish a V0 MP3 from the 320kbps MP3?

I know *I* sure as hell can't tell the difference between 320 CBR and V0 VBR LAME MP3s. I can usually tell a slight difference between these and lossless (mostly in cymbals and that high-range sparkle effect is where MP3 is most noticeably lacking compared to lossless or even OGG), but it took some significant gear to reach that threshold where it makes a difference.

I doubt there's any audible difference between MP3 VBR 0 and CBR 320, at least not that's worth measuring. If you need audible improvement over VBR 0 while sticking with lossy, switch to Ogg -q8 or higher (again, cymbals have more sparkle).

I just stick to FLAC these days, though. At least then I know I'm getting the best that the recording has to offer, and given that most of my listening is now desk-bound in a quiet environment, the differences are more evident.

And technically speaking, CBR is a waste. It's like running an engine at full throttle at a stoplight. Dumb.