<font color='#000000'>I have a similar setup in my A/V room, with my couch placed against the back wall that is approximately 14 wide. I placed my speakers about 1 foot away from the corner, at a height of approximately 1 foot above my seated head position. This is the setup recommend by Dolby.
My head position is slightly in front of the speakers due to the depth of the couch back.
My rear speakers are Sapphire dipoles, with angled tweeters. www.sapphireaudio.com
I recommend drilling into the mortar rather than the brick. It is cosmetically much easier to fill in a little mortar than to attempt to plug a hole in a brick. Use a proper masonry drill bit.</font>