Specify audio channel to write to monaural file using SoX

Question

I am interested in using SoX as part of a transcoding workflow I'm building. I need to be able to downmix stereo audio streams to mono. More specifically, I need to be able to specify which channel to write into the output file. As best as I can tell, the syntax should be as follows:

sox infile.wav -c 1 outfile.wav avg -l

However, when I issue the command, I get this error:

sox: invalid option -- l
sox: SoX v14.3.2

sox FAIL sox: invalid option

Stumped. Any ideas?

EDIT: Here's the command that does what I want.

sox infile.wav outfile.wav remix 1

Answer 1

There's no valid -l option. You could try it with the option "remix" or "oops". Both are listed in the documentation http://sox.sourceforge.net/sox.html#EFFECTS