studioviols
New member
A discussion of VBR.
definition - Variable Bit Rate is an MP3 endoding scheme that vary's the number of bits of data, (more bits versus fewer bits), used to encode a specific time unit of an MP3.
For Example :
If in my soundfile, I have 5 seconds of violin playing the same note and holding that note across those 5 seconds, far fewer bits of data will be used to represent that 'noise' in the file, than 5 seconds of full orchestra with 2 guitars and a choir.
If I set the VBR rate low, the 5 seconds of violin playing may take, (a rough estimate), 40k bits, (NOT BYTES), to be represented in the file, whereas if I set the VBR high, the violin would take far less, perhaps approximately 12k bits.
Whereas the 5 seconds of full orchsestra, guitars and such would take perhaps 150k bits if I set VBR at a high level, and perhaps 30k if I set VBR at a low level.
And in contrast to all of that, if I used NO VBR, and set the bit rate as constant, then both 5 second section would use the same amount of bits.
I have noticed in user statistics from some sites that I host my MP3's on that MP3's at greater than 192kbps have a far lower incidence of successful streaming to completion than those saved at 128kbps and lower. I see this in statistics represented by a user who begins to stream, and then 5 seconds later streams again, I am assuming the stream cut out and they are attempting the stream once again.
ALSO
I have noticed that streams where the encoding is done with a very high VBR or 'Variable Bit Rate' cut out more often than any, and
ALSO
Microsft's Windows Media Player exhibits some clicks, snags and gurgles during playback for MP3 encoded with VBR, the higher the VBR the worse the playback.
I am playing back on a dual processor machine with very fast drives and still, nastyness ...
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01.
ARE YOU HAVING PROBLEMS WITH VBR and if so ... what kind o' probs ? Local problems ? Streaming problems ? both ?
02.
Do you believe VBR rate setting tweaking during MP3 conversion can preserve high end of the violin in the above scenario ? Or would it be worse, and the encoding scheme attempted to use as few bits as possible for that section of relatively less complex sound, thus sacrificing from the high end first anywayzzzz ... ?
definition - Variable Bit Rate is an MP3 endoding scheme that vary's the number of bits of data, (more bits versus fewer bits), used to encode a specific time unit of an MP3.
For Example :
If in my soundfile, I have 5 seconds of violin playing the same note and holding that note across those 5 seconds, far fewer bits of data will be used to represent that 'noise' in the file, than 5 seconds of full orchestra with 2 guitars and a choir.
If I set the VBR rate low, the 5 seconds of violin playing may take, (a rough estimate), 40k bits, (NOT BYTES), to be represented in the file, whereas if I set the VBR high, the violin would take far less, perhaps approximately 12k bits.
Whereas the 5 seconds of full orchsestra, guitars and such would take perhaps 150k bits if I set VBR at a high level, and perhaps 30k if I set VBR at a low level.
And in contrast to all of that, if I used NO VBR, and set the bit rate as constant, then both 5 second section would use the same amount of bits.
I have noticed in user statistics from some sites that I host my MP3's on that MP3's at greater than 192kbps have a far lower incidence of successful streaming to completion than those saved at 128kbps and lower. I see this in statistics represented by a user who begins to stream, and then 5 seconds later streams again, I am assuming the stream cut out and they are attempting the stream once again.
ALSO
I have noticed that streams where the encoding is done with a very high VBR or 'Variable Bit Rate' cut out more often than any, and
ALSO
Microsft's Windows Media Player exhibits some clicks, snags and gurgles during playback for MP3 encoded with VBR, the higher the VBR the worse the playback.
I am playing back on a dual processor machine with very fast drives and still, nastyness ...
-------------------------------------------------------------------------------
01.
ARE YOU HAVING PROBLEMS WITH VBR and if so ... what kind o' probs ? Local problems ? Streaming problems ? both ?
02.
Do you believe VBR rate setting tweaking during MP3 conversion can preserve high end of the violin in the above scenario ? Or would it be worse, and the encoding scheme attempted to use as few bits as possible for that section of relatively less complex sound, thus sacrificing from the high end first anywayzzzz ... ?
...... I have had problems like those mentioned w/ VBR however. And, as mentioned above, I think its important not to goose the vbr too hard. When i convert to mp3, i run at 256 with a "medium" setting on the CDXtractor (thats the one i use btw.....). It uses the Lame encoder which is also important. The "medium" setting controls (at least to my understanding) the variable curve of the vbr. I have found that when i push this curve too hard toward the upper end, i start to get more evidence of artifacts, and unstability.