Variable Bit Rate

[wylton]

I find myself downloading a lot of music these days, and obviously take the highest quality I can get; Flac if it's available else the highest bit rate on offer. Occasionally I've found two options 192kbps or VBR. The 192kbps files are bigger, so I assume they're better; is there any inherent disadvantage with VBR files?

As long as the music is good, I find that I'm happy to live with lower fidelity;there is such a lot of good free stuff out there these days.

 

[Nik]

I find myself downloading a lot of music these days, and obviously take the highest quality I can get; Flac if it's available else the highest bit rate on offer. Occasionally I've found two options 192kbps or VBR. The 192kbps files are bigger, so I assume they're better; is there any inherent disadvantage with VBR files?

As long as the music is good, I find that I'm happy to live with lower fidelity;there is such a lot of good free stuff out there these days.

VBR means that the bit-rate varies with the complexity of the music, so you make better use of the total size, but comparing the size doesn't mean much unless you know what the "base" rate is for VBR. I used to use 160k VBR in iTunes and the average bit-rate generally came out at around 200k, so it was using 160k as a minimum, not an average. This would have to be quite a lot better that 192k CBR, which must "waste" lots of bits. I'd guess that VBR files could be smaller than CBR without losing any quality, but by how much I don't know.

 

[wylton]

VBR means that the bit-rate varies with the complexity of the music, so you make better use of the total size, but comparing the size doesn't mean much unless you know what the "base" rate is for VBR. I used to use 160k VBR in iTunes and the average bit-rate generally came out at around 200k, so it was using 160k as a minimum, not an average. This would have to be quite a lot better that 192k CBR, which must "waste" lots of bits. I'd guess that VBR files could be smaller than CBR without losing any quality, but by how much I don't know.

OK, thanks for that, I'll just settle down and enjoy the music then!

 

[amdismal]

There are different VBR settings, see here: http://lame.cvs.sourceforge.net/viewvc/lame/lame/USAGE

In general, VBR will be better than CBR at the same bitrate, as the variability allows it to spend more effort on more complex passages and less on, say, silences. But that is rather a general statement, it can be a lot more complex than that. But as long as you are 192 or above, it's pretty good. I am unconvinced that I could reliably pick out >=256kbps MP3s that have been well encoded, even on my system that is pretty revealing.