I thought this would be an easy question to find the answer to but I seem to not be able to find this anywhere.

HD channels sound VS analog TV sound

My HD Channels that I get with my basic cable (ABC, NBC, CBS, Fox) clearly have a distinct left and rear channel so I'm guessing the sound broadcast is Dolby Digital 5.1? Or does it vary by channel? Any of them 7.1 or more channels?

Analog TV channels produce less sound from the rear speakers if any at all. Appears to be in mono from the rear speakers and limited frequency range. Would this be Dolby Pro Logic? Isn't Pro Logic the best surround that you can hope to get from analog TV and from VHS tapes?

HDTV is always DD, but not always 5.1. Analog TV is always mono or stereo. Cable and sat channels can be in stereo or 5.1 depending on the source. How those are reproduced on your setup depends on your setup and what decoders you use.

It mainly will depend on the decoder you gonna use
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It mainly will depend on the decoder you gonna use
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