M4A exporting

Hi Guys,

I am mostly exporting editing from Audacity to m4a, but now, with v2 I see just a quality slider:
Before there was a normal config, just like with mp3 format. Is this new format option aimed to prevent any upsampling?

I am using 2.2.0 version.

It seems it tops at 192kbps, I have tried to re-done som flac and even with a quality set to 500 it was just 192kbps. How can I get 256kbps sample rate?

And I have forgotten to mention, after export and checking the file through MediaInfo it says “192kb/s, 44,1 kHz, 2 channels, AAC (LC)”.

I don’t use M4A myself, but from the Release Notes:

M4A (AAC) exports: > The Quality Slider in “Specify AAC Options” has no effect if the FFmpeg library is built with the libvo-aac encoder, as are recommended builds of FFmpeg for Windows and Mac OS X. Workaround: You can specify a constant bit rate if you select “Custom FFmpeg Export”. Click the Options… button, choose “mp4” in the formats list and “libvo_aacenc” in the codecs list, then set bit rate in bits per second. Up to 320000 bps (320 kbps) is supported. Given the alternative AAC encoders for FFmpeg also have problems as described in these notes, you can instead export as WAV and convert to AAC in iTunes on Windows and Mac.

The second workaround sounds best to me (export as WAV and convert to AAC in iTunes) and has the added benefit that it gives you a lossless format backup version.
If you don’t use iTunes, and you don’t want to install that monstrosity, then you could use the excellent free “foobar 2000” instead: http://www.foobar2000.org/