going from 7.1 to 9.1
I have referred to the forum over the years, and finally set up an account. First post, please forgive any mistakes. My question revolves around my new Marantz sr7011 and expanding my 7.1. setup. Along with the Marantz (always been an Onkyo guy. So far I am loving the Marantz, but I am off topic) I have a 7.1 THX Select 2 piano black Crystal Acoustic speaker setup, 2 towers, center, 4 dipoles, and 12 THX sub. My room config, (3 walls and the left side is open) Seated area is approximately 15 feet from screen. I have the surround right and left(is on a bookcase) mounted about a foot down from the ceiling inline with my seated listening spot. My 2 back surrounds are also at the same height 2 feet behind the seated spot.
My buddy just gave me 2 Boston micro 130x 8ohm speakers. I would like to take advantage of what the Marantz has to offer and expand my 7.1 (Dolby Atmos/DTS-X,Auro 3D). I can NOT mount anything to the ceiling. What is the best use/placement for these 2 new speakers? Do I need actual Atmos speakers? The up facing Atmos speakers won't work for me as my towers have the external tweeters on top. Can I use the Bostons in the front high positions and tilt them up? My main use for the this room is tv/movies/gaming.
Thanks for taking the time to read, and for any input. I tried a ton of searches, but hit a grey area on expanding 7.1 by 2 speakers.