Created attachment 664 [details]
Mockup of how the dialog for WAV export would look

In the Export Audio dialog (and similarly, but slightly different, the Export Multiple dialog) we have entries for WAV 16-bit PCM and WAV 32-bit float PCM.  We added the 32-bit WAV fairly recently as folk had trouble finding it.  

We now find that folk are struggling to find the 24-bit WAV export (see this Forum thread http://forum.audacityteam.org/viewtopic.php?f=46&t=89986 ) as it is "hidden" in the "Other uncompressed files" entry in the "Save as type" dropdown menu.

Steve and I discussed this and we would like to propose that we change this so that the "Save as type" dropdown menu has a single entry for WAV and that the "Format options" box be used for selection of the "Encoding" - see mockup dialog attachment.  The default setting would of course be 16-bit WAV, but the Export would "remember" the previously used setting - and note carefully that we have two different settings one for Export and the other for Export Multiple and that having two is useful and should be retained.

Teis would have a number of advantages:
1) make the 24-bit WAV option more readily "discoverable"
2) reduce the command-coun the the "Save as type" dropdown menu
3) utilise the "Format Options" box for something useful (currently it says "No format specific options.
4) One can still clearly see which encoding is to be used with the WAV export

If we do do this then we should do similar for AIFF at the same time.

I have assigned this to Leland for now as he did the previous modification work to these dilaogs for 2.1.2