[LAU] Command line to combine stereo WAV into 4-channel WAV?

[Ken Restivo]

Is there a bit of command-line-fu that could be used to combine two 2-channel WAV files into a single 4-channel WAV file? In batch (I have a bunch of these to convert).

I suppose I could load up Ardour, import the files into Ardour, make tracks for them, place them on the tracks, set my start and end markers, then export a mix.... btu there has to be a one-liner somewhere (sox? sndfile-convert? something?) that'll just do it.

Thanks.

-ken