Onkyo TX-SR504 w/ DTS HD & DD TrueHD

I have an Onkyo TX-SR504 which is a pretty basic DD/DTS receiver. It has 5.1 analog inputs. It is my understanding that I can use these analog inputs in the receiver to get DTS HD & DD TrueHD (lossless formats) from my Toshiba HD-A1 HD-DVD player.


The HD-A1 will only decode 5.1 of the 7.1 channels of DTS HD/DD TrueHD. That actually works out ok for me because my receiver only has 5.1 ch analog inputs, not 7.1 ch analog inputs. So (through the analog inputs) I should receive uncompressed 5.1 ch audio on my receiver. What format will my receiver see this audio signal as? If it see's it as a Dolby Digital or DTS or a regular stereo signal, I should be able to apply PLIIx to it and get 7.1 uncompressed audio. Will my receiver allow me to apply PLIIx to the audio?


Also, since the HD-A1 can only decode 5.1 of the audio channels, what if I put in a DVD that has 7.1 channels? Will it take the audio that should be sent to the rear surrounds and use it as a phantom image in the surround sides? If that is the case, then I can just use PLIIx to get 7.1 out of it.


When/if I apply PLIIx to the uncompressed audio, will it lower the bit rate or anything like that? Would there be any disadvantages to applying PLIIx to an uncompressed 5.1 ch audio signal?



Thanks