Convert Stereo to 3.0
Reply #1 –
CenterCutGUI can do that. It will create two audio tracks: a mono Center one and a stereo Side one. Center will be whatever info is "the same" between Left and Right. Side will be the difference. You can also select to send the bass info to the center or to keep it in the front channels. I would recommend do both, so every channel has bass.
Later