7.1 discrete channel surround sound

Hi,

This is with regards to 7.1 discrete channel DTS-HD MA or Dolby TrueHD Bluray disc. When such 7.1 discrete channel are on the disc, what are the speakers that are intended from the last(?) 2 channels. Are they meant for the rear speakers?

I am curious because what happens if someone set up their 7.1 speakers as front height? Assuming that no processing eg Dolby Digital IIPz or Audyssey DSX invoked in this case, will the the last two channel be ignored as no rear speakers are hooked-up. Are there no sound from the front height speakers? :dontknow:

What happens then, when using either DD IIPz or Audyssey DSX? Will these mode make use of the last 2 discrete channels to output to the front height speakers? From an audio perspective, this could be quite the opposite effect of the intended material eg. sound from the rear now coming out from front height speaker instead.

Am asking this as I have a choice to wire my speakers as rear or front height - want to know what is the best choice to make use of all the 7.1 discrete channel sound on a Bluray disc.

Thanks a lot and if this is seems like noob question - yes, I am a complete newbie :doh:to Home Theatre.