When exporting (multiple tracks) you can choose between Interleaved, Mono-Downmix, etc. When “Interleaved” is selected, all files will be exported as stereo, no matter if they are mono. Its the other way round, when “Mono-Downmix” is selected, then all files are exported as mono.
It would be great if there would be an additional “standard” mode to export the tracks as they are.
If the track is a mono track, export it as mono, if it is stereo, export it as stereo.
Right now, you cannot do both exports simultaneously. You need a separate export for each.
i just tested this, and exporting a combination of mono tracks and stereo tracks as “interleaved” will result in the mono tracks being exported as mono and the stereo tracks as stereo. I checked by doing an export mixdown, then importing the resulting tracks. I then compared them to doing the mono tracks as mono, etc. So it is already doing what you want it to do!
On export dialog select “export as: interleaved” and “effects: Disabled (DRY)” option in order to export both mono and stereo files simultaneously.
All other options result only mono or only stereo files.
