I have a bunch of audio files generated by an application that recorded one channel only (mono). I normally go in by hand in Audacity to
amplify as much as possible without clipping
copy the one channel into the second channel to make it stereo
Is it possible to put this into a chain so that I can apply it automatically to a lot of files? Which chain elements (nyquist or whatever) can I use to amplify as much as possible and to make it stereo? I’m using Audacity 2, on Mac OS 10.6, and I installed from the .DMG.
As far as I’m aware, the only way to do that is to use an external program to handle the export (http://manual.audacityteam.org/o/man/exporting_to_an_external_program.html) and supply appropriate command line options to that program so that it produces a 2 channel output.
Why do you need to do that? A 2 channel mono recording should sound identical to the single channel track, but requires twice as much disk space.
That will happen if the “mono” file is a 2 channel (stereo) file with sound in one channel and silence in the other. It will not occur with one channel mono files (unless something else is broken, such as one of your speakers not working, but you would then notice the same problem with stereo files.)
Stereo files with silence in one channel can occur if you record a mono source (such as a single microphone) as a 2 channel (stereo) track. This will sometimes (depending on the sound card and sound card drivers) produce audio in the left channel and silence in the right channel.