MP3 not showing correct VBR after Export

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sblaise4
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MP3 not showing correct VBR after Export

Post by sblaise4 » Tue May 19, 2015 11:12 pm

I've exported a song in MP3 format, Extreme Preset: 220-260, and in the folder it shows 606kbps. Is this normal?

kozikowski
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Re: MP3 not showing correct VBR after Export

Post by kozikowski » Tue May 19, 2015 11:48 pm

You need to help us out a little bit. Start with the information in the pink band above and then on to the show you're trying to compress. Stereo? Mono? Duration?

Koz

DVDdoug
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Re: MP3 not showing correct VBR after Export

Post by DVDdoug » Wed May 20, 2015 12:39 am

Deja vu.

FYI - MP3 only can't go higher than 320kbps.

Robert J. H.
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Re: MP3 not showing correct VBR after Export

Post by Robert J. H. » Wed May 20, 2015 5:05 am

DVDdoug wrote:Deja vu.

FYI - MP3 only can't go higher than 320kbps.
That's a myth.
You can go up to 640 kbps but no player can play it.
However, you can use the --freeformat switch in order to archive your files and re-import them into Audacity.

On export, choose "External Program".
Under options, you can specify your own format such as:

lame -m m --cbr --freeformat -b 640 - "%f"

There are of course better settings--those that can be read by an arbitrary player.
-b means the minimum bit rate to use and
-B the maximum

An overview over the switches can be found here:
http://ecmc.rochester.edu/ecmc/docs/lam ... freeformat

Don't be to concerned about the average bit rate.
If there's a lot of silence in the file, 32 kbps are used.
There's also the bit reservoir that takes some burden off the actually required bit rate to achieve the given quality setting.

Robert

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