FFAStrans supports sophisticated audio channel mapping from the source to the output.

Track/stream <no. >

The number of discrete tracks dependent on the"Discrete tracks" settings. So if you have selected 2 discrete tracks, you can map what ever source channels you like to those tracks. If you specify source channel(s) that does not exist, it will be replaced by a silent channel. The notation for channels mapping is either integer numbers or variables separated with a comma (,) but pipe (|) and semicolon (;) is also supported as separators. The number of channels specified in the strings will determine the number of channels per discrete track.

Example:

Specifying "1,2,3,4" in an input field will give 4 channels in one track, starting from the 1'st channel found to the 4'th.

As stated, variables are also supported, either as separate channel representation or a complete set of channels.

E.g. if %s_channels% = 3,4,5

Specifying "%s_channels%,2,1" in an input field translates to input channels "3,4,5,2,1". This would give 5 channels on one track.