Originally Posted by sdurani
The decoder doesn't unpack/decode the entire Atmos soundtrack (objects and all) only to then downmix it back to 7.1 when there already is a 7.1 channel core in every Atmos track that can simply be sent to the 7.1 speakers. Again, anyone can write to Dolby to verify this.
Please correct me if my "logic" is flawed,
If there is an Atmos placed "object" clearly in my Rear Left Height speaker, that's were I hear it in my 7.1.4 setup.
All my bed layer speakers are at ear level, the heights are 4 feet higher so I can tell the difference.
If said "object" is to be heard in a 7.1.0 speaker arrangement without a designated height speaker to play it,
it will either be heard in the left surround back, left surround (or both) regardless of whether its decoded as Dolby TrueHD or Atmos.
The "object" that would have been placed in the height designation is not eliminated from the sound track,
it's simply directed to the speakers it does have access to (down-mixed).
The same way a 7.1 bluray can still be heard in its entirety by someone with a 5.1 speaker setup.
Surround Back information just gets moved to the surround channels.