Program for converting to 16bit

Anyone know if a program that can convert multiple wav/mp3 files to 16bit?
I use Adobe Audition most of the time, but far as I know you can't edit/convert multiple files simultaneously.

Audition has a batch convert, will perform any process. If it's not there, activate it via 'Window > Batch Process'

For 24 to 16 bit conversion, hit Export Settings. You can also apply any 'Favourite' effect preset.