Pro logic II player vs Dolby Digital player

[Iwanttoknowmore]

1. When a 5.1 Dolby Pro logic II Home theater player plays a 5.1 Dolby Digital DVDs, is the result same as in Dolby Digital player? If not, why? because the 6 channels in Dolby Digital DVDs are discrete so the Pro logic II player will not have to do any approximation!
2. Can a 5.1 Dolby Digital player play VCDs?

 

[americanaudiophile]

1. There is no such thing as a Pro Logic Player. All DVD and BD players will play 5.1 Digital if the disc has multichannel audio. You do have to connect them to your AV system with a digital connection or a 6 channel analog connection. If the disc has only 2 channels or you connect with a 2 channel connection then you will only be able to get surround sound by letting the AV system synthesize it with Dolby Prologic codecs.
2. Depends on the player. Usually this is stated in the specifications.

 

[kanewolf]

A pro-logic II decoder will take two channel audio and synthesize surround sound from it. A pro logic II decoder will not give the same results as a 5.1 source played through a 5.1 decoder. A 5.1 Dolby Digial decoder will take multichannel digital data and split it to multiple analog channels. I am not sure this answers your question ...

 

[Iwanttoknowmore]

Yes, I guess I got the answer for Q1. The decoder will down-mix and create "a two channel, Dolby surround-encoded mix for playback over the home theater system with 5.1 Dolby Surround Pro Logic II decoding". So it will not convert 6 channels into 6 rather it will go like down-mixing first then up-mixing: 6 ch >2 ch >6 ch. So 4 of the 6 original channels will be lost, thus the quality will be compromised. But I just got this from the Dolby's site and I need confirmation on my understanding.