Movies in the 70's & 80's was it stereo or mono?

depends on the film.

Mitch - that particular movie will play in it's original mono sound format. The movie's original mono soundtrack was encoded into Dolby Digital for use on the DVD. Dolby Digital may be scaled from mono up to 5.1 discreet channels depending on the source.

You may want to try a few of the DSP modes in your processor to get some simulated ambiance. My receiver, for example, has a DSP mode called "mono movie" which is actually a pro-logic mode that gives mono sources some extra ambience. Running it through Pro-Logic II movie mode may give you a pretty good simulated surround ambiance, but just like processing stereo music into surround, your results will vary depending on the source material. Cheers!

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ok.....thanks John
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