you can only get proper DTS-X sound if it says so on the back of the bluray box where it lists the soundtrack options, the Force awakens bluray has only a standard DTS-MA 7.1 mix.
the latest Jason Bourne film and Despicable me 3 have true DTS-X soundtracks on the standard bluray.
Can you let us know what make and model number your a/v amp is as it helps us on the forum answer your questions better.
*music2*