I use this command to merge two audio files into one using sox:
sox end.mp3 -p pad 6 0 | sox - -m start.mp3 output.mp3
I was wondering how can I merge 3 or 4 audio files using only one command instead of using the "output.mp3" as the input to the next command and so on?
I will really appreciate any help
You can do it with one invocation of sox like this:
sox -m in1.mp3 in2.mp3 in3.mp3 out.mp3
If you want to combine this with the pad effect you need to be clearer about what you want.
To combine mix and effects (pad, trim etc) use the following:
sox -m "|sox end.mp3 -p pad 6 0" start.mp3 output.mp3
The general pattern is:
sox -m input1 input2 ... inputN output
where inputX can be either a filename or a pipe in quotes
"|sox end.mp3 -p pad 6"
来源：https://stackoverflow.com/questions/14634036/how-to-merge-several-audio-files-using-sox