It would be a helpful starting point for you to differentiate among the various options on A/V equipment.
http://en.wikipedia.org/wiki/Surround_sound
http://en.wikipedia.org/wiki/DTS-HD_Master_Audio
http://en.wikipedia.org/wiki/Dolby_TrueHD
Pro Logic can sound wonderful compared to typical stereo sound from TV speakers, but it's no substitute for the real deal (digital discrete, DD5.1 and higher), which does not sound as 'hollow' as Pro Logic. Compare what you hear via Pro Logic with DTS-HD or Dolby True HD and you get a better sense of what is possible by employing a newer A/V receiver, better speakers and a blu ray device.
hth,
Pedro
p.s. although it's more complicated, I'd still encourage you to let your cable box & receiver handle the audio instead of optical out from the TV. You'll generally do better this way.
Finances and family...wrong forum? (LAST 2 PARAGRAPHS MY BE ALL YOU
NEED TO READ!)
Well, that's how it came to be that I started computing with Win 95, and next leap was Win XP!
Likewise, I had been using an analog Dolby surround decoder for years (and years!) I was very pleased when it worked right. Then came Comcast Digital box. (first NON-HD) This killed the workings of my cheap little decoder. Think I know why, so let's move ahead.
I then made the leap, from analog surround, to HDTV- now WITH Comcasts HD box service, and a new 5.1 surround amp., a Yamaha brand. I was impressed with the fact that almost the entire back was nothing but holes!, to plug something into!
I began purchasing the needed connection cables, a few at a time to spread the cost around.
Then it occurred to me. Why split the HDMI from cable box to TV? At this point my 2 DVD devices have no HDMI outs. And I hate losing the full functions of a device - my TV in this case. The TV needs to do all it can do, (for all the family) - without having to turn on the Yamaha, involving another remote and training sessions, cheat sheets, etc.
I gotta cut this, so end result is I have to pick up the Comcast remote, change AUDIO input to TV, to HDMI - from Dolby Digital.This kills the sound to TV speakers! Then the Yamaha indicates it is getting a 5.1 surround signal from the TV outs - Fiber optical.
>>>> OR.......... I simply change the surround decode type of the Yamaha to "PRO LOGIC" and leave it there. Now, anytime the amp is turned on, surround sound is absolutely discrete, sounds great- no having to mess with another remote, and cable setting changes - only to have to undo it for general (family) TV use without amp on.
I have an ear (actully , 2). I hear the discrete sounds coming from left and right, and rear, as they are in sync with images on the TV.
So, how is PRO LOGIC considered........fake?
Help me out.

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