Watching old movies in mono

Recently I have been watching classic movies and the soundtrack is in mono when it is indicated as stereo. Hence only one speaker is used - the centre speaker.

In order to utilise all the speakers, I turned on “all channel stereo” as I felt that it’s a waste not using the rest of the speakers :grin:.

May I know what type of processing do you use when watching a movie in mono?

I believe Anthem has a DSP for mono content?