Thunder Bird wrote:
Musikone
I've revisited the problem and have found I can convert as I did before by altering 2 values
Minimum Bitrate was increased from 16 to 32 kbps
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This is indeed _critical_! These parameters cannot be chosen arbitrarily; they are inter-dependent. Yes, you have to go up to a minimum bit rate of 32 kbps before you can both get a stereo conversion and retain the sampling rate of 44.1 khz. Have you tried this with a bit rate of 24kbps instead of 32kbps?
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Quality was reduced from 2 to 3 and everything is now working as before
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I have not checked out the inter-dependence of "quality" with these other parameters.
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As I had not written these values down I was doing it from memory
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Here is the hitch. The moral to this story is not to make off-the-cuff statements without _written_ results, so that when challenged by curmudgeons such as myself, you will not come away with a red face!
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Did not think reducing Minimum Bitrate from 32 to 16 kbps would be so critical
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Repeating: what is critical is to take notes and avoid making casual statements of "fact," unless of course you acknowledge with that there is a question as to certainty. Unfortunately, you ran into a highly experienced and very-well-educated ELECTRONIC ENGINEER (as well as a musical scholar and performer on the side), and an experienced TEACHER, to boot.
Oh well; things are seldom what they appear to be in the Wonderful land of Oz :-)
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Or increasing quality from 3 to 2 either
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As I said, I have not researched this aspect of the conversion process. For some time I used a quality level of 2 in my VBR conversions, but switched to 0 not too long ago, since I am willing to trade a slightly larger file size for superior audio quality.
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Original file was at a variable bitrate - Maximum Bitrate (320 kbps) - No idea on Minimum Bitrate
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You didn't say this in your post. I assumed that the number which you gave was a _constant_ bit rate. It is assumed, by default, that a bit rate stated without any mention of a minimum bit rate is a constant bit rate. Here again, it is very important to be precise--when you are dealing with an engineer-teacher type!
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Changing the 2 values mentioned above my 320 variable bitrate MP3 file conversions to 112 variable bitrate
are now producing stereo MP3 files
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Yes, I know :-)
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The original file's sampling rate was the "standard" 44.1 khz
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Just as I presumed.
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This same sampling rate has been preserved through the bit rate conversion process
(Had to reduce Quality from 2 to 3 to preserve this value)
Raises the question what is the lowest maximum bitrate coupled with the lowest minimum bitrate you can use
and still produce stereo MP3 files (not forgetting the Quality setting)
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I don't know. I would suggest that you determine the answer--by experimentation.
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Thank you for your help
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You're welcome.
Hopefully you have learned a lesson about the need for_precision_ in technical matters. But don't feel too bad about this; you are hardly alone in this forum. In fact, you are in the overwhelming majority here. Where you differ, and this is to be commended, is in your very quick response to my challenge. Most folks around these parts simply melt away when under fire.
Musikone
[Gotcha with this moniker, didn't I? :-)]
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