I have a bunch mono .wav files which I need to convert to stereo in order to run thru lame. Lame can't encode stereo mp3s from mono input so that's what I need to do.
I don't need any modifications to the data made other than duplicating channel into two.
I've tried to use
sox and it seems to alter sound data in eerie ways by up-downsampling and changing bit depths in between as well as running filters I don't need.
So please recommend me some tool to batch convert .wav files from mono to stereo. I'm on linux.